MORE TWIST

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  • Last Post 22 August 2018
joeb33050 posted this 30 July 2018

Just back from the range, M110 Savage barrel, Hornady 55 gr fmjbt cannelure;

7/Titegroup, 5 shots in 7"

8.5/Titegroup, 5 shots in 4.75"

and NO tipping.

This twist/stability business gets stranger the more I shoot. 

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Ken Campbell Iowa posted this 30 July 2018

... didja happen to shoot a few " known good " loads ...    my tikka/ithica 308 shoots only about 6 moa with gov't bullets that look just like those hornadys ....

ken

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Scearcy posted this 30 July 2018

Unfortunately stable bullets do not guarantee accuracy. I have never had much luck with the Hornady FMJ but do have to agree that a 7" group is noteworthy.  Keep going! It is nice to see data.

I just opened my 5th box of 6MM gas checks since I bought my first 243 Thanksgiving week of 2016. Since my first "accurate" 243 has a 260 mm twist, I spent the first 15 months trying to find a way around the basic principles of stabilizing a bullet. I learned alot but I was not able to answer all of my questions. I was also unable to circumvent the mathematics. I have 5 different molds which produce bullets which fit one or more of my current crop of 243s. Only 2 or 3 combos produce good accuracy and in all cases the twist rate suits the bullet. Velocity, within our normal cast bullet ranges, never helped stabilize a bullet as much as I expected (hoped).

Jim

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OU812 posted this 30 July 2018

The Sierra 52 grain match bullets shoot well in my 223 rifles using Titegroup. I also like using Moly coating to reduce copper fouling.

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Scearcy posted this 31 July 2018

Hornady 50 gr Vmax seem to shoot well in every rifle also.

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Ken Campbell Iowa posted this 31 July 2018

i did not mean to disparage hornady in my above query ... in fact, me here and my rifles mostly favor hornady bullets.   i was just wandering that perhaps hornady ... and others .... pay a little less attention to bullets meant for bulk use by the pray and spray foks.   i once had a box of perfect-looking mj 224 bullets that shot 6 moa in my remmy 222 that otherwise never shot over 1.5 moa in it's life.

ken

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R. Dupraz posted this 31 July 2018

Nothing wrong with Hornady. However, used to be when I was after serious accuracy with jacketed, Sierra got the nod.

Don't know how it is any more as I haven't bought any jacketed for some time now. 

 

R. 

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John Carlson posted this 31 July 2018

Hornady, Sierra, and the old wide mouth Speer 52gr hollow points have all shot well in my 223s but when I want serious accuracy I go to Berger.

John Carlson. CBA Director of Military Competition.

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joeb33050 posted this 31 July 2018

... didja happen to shoot a few " known good " loads ...    my tikka/ithica 308 shoots only about 6 moa with gov't bullets that look just like those hornadys ....

ken

No, but I did shoot some 40 gr Nosler hp, groups were fair. I haven't shot this barrel much, and will sell it. The 22" sporter bbls like this don't shoot as well as the 26" heavy bbls.

I see big groups/no tipping; small groups tipping and sideways, I can't get a handle on this.

 

Anyhow, the idea was to see if jacketed shoot small groups with cast powder and no fiddling = weighing powder, fretting about oal, turning necks, weighing/sorting cases. orienting anything. They do.

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RicinYakima posted this 31 July 2018

So, are we at the hypothesis that stronger bullets are more accurate than weaker bullets yet?

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Brodie posted this 31 July 2018

 I think that the hypothesis is more :  twist and velocity how fast to best stabilize the bullet.

B.E.Brickey

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joeb33050 posted this 02 August 2018

So, are we at the hypothesis that stronger bullets are more accurate than weaker bullets yet?

All I* know is that JB groups < CB groups, mott.

 

CBA NM groups haven’t changed size in 20 years.

 

Is it easy to shoot jacketed .22 bullets In the 5-shot 100-yard average between .5” and 1” area, using a CB Powder, (Titegroup), and charge?

 

Yes. I have done it and can do it.

 

M110 Savage barrel, 12” twist

 

Hornady 55 gr fmjbt cannelure;

 

7/Titegroup, 5 shots in 7"

 

8.5/Titegroup, 5 shots in 4.75"

 

and NO tipping.

 

I shot some 40 gr Nosler hp, groups were fair/poor.

 

Probably barrel and twist at fault.

 

8/2/18, Shilen 9” twist 22-250, group size “

 

Nosler 40 gr., 7 Titegroup , .7, .8, .9, 1.1; avg. .875//8.5 Titegroup, .6, 1.1, .8; avg. .800

 

99% of CB shooters would be delighted to shoot these groups.

 

Hornady 55 gr fmjbt cannelure; 1.5, 1.475, 1.475; avg. 1.483//8.5 Titegroup, 1.1, 1.875, 1.075; avg. 1.35

 

The Hornady bullets are inexpensive, weighed, 55 +/-.1 gr selected, others sighters.

 

So, not all jacketed bullets shoot accurately; something makes them inaccurate.

 

What is it?

 

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joeb33050 posted this 02 August 2018

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pat i. posted this 02 August 2018

Joe just as an aside have the groups shot at the Super Shoot improved that much in the last 20 years? I know some of the records are pretty old. Have there been major improvements in ASSRA groups in the last 20 years? Have Rimfire shooters made great strides? High Power? BPCR? Air Guns (probably)? All the other shooting sports? It's all about the bullet and some just aren't good. A good cast bullet will out perform a poor jacketed bullet but a good jacketed bullet will run rings around the best cast bullet. Simple as that.

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beagle6 posted this 02 August 2018

Why is all this on the CAST BULLET forum? If I was interested in jacketed bullets, I would be on a different web site.

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pat i. posted this 02 August 2018

One of the great mysteries of cast bullets to some people is why they don't shoot as well as a good jacketed bullet let alone a premium BR jacketed bullet made in a good die with J4 jackets. Besides that I look at it as just making conversation.

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Scearcy posted this 02 August 2018

+1

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RicinYakima posted this 03 August 2018

Joeb is looking for "Why". More power to him, and for me it is fun to read his trials and tribulations. For us it is the "exploring" as much as the finding.

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Ken Campbell Iowa posted this 03 August 2018

shooting some good mj bullets sets a baseline for that rifle .... necessary if you are seriously trying to learn about making cast bullets shoot better .  

and also joeb's work is valuable in that it has shown us that we can expect a valid baseline by using similar charges with mj as with our cast bullets to be tested.

after a day of shooting 3 to 12 inch cast groups, it is helpful to try a few mj ....... ::  yep, those cast loads really were that bad .....

ken

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joeb33050 posted this 03 August 2018

Joe just as an aside have the groups shot at the Super Shoot improved that much in the last 20 years? I know some of the records are pretty old. Have there been major improvements in ASSRA groups in the last 20 years? Have Rimfire shooters made great strides? High Power? BPCR? Air Guns (probably)? All the other shooting sports? It's all about the bullet and some just aren't good. A good cast bullet will out perform a poor jacketed bullet but a good jacketed bullet will run rings around the best cast bullet. Simple as that.
Pat;
All  know about is ASSRA; we were shooting at WNYSS/Alabama NY when Jerry Ventura shot the first 200 yd 250 score, 10 shots with CENTERS in a 1.75 "25". (Surely Frank will correct this.) That was late '80s?
Since then 250s are commonly shot. I believe that we/they went from  old ballard/hiwall/Hepburn/stevens bbls to modern-made bbls and the bbl made the difference= lotsa 250s.
I don't recall ANY CBA change like that, equipment-technique or method. 

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pat i. posted this 04 August 2018

You know a heck of a lot more about ASSRA matches than I do but a quick check of the CBA records shows the 200 yd score PB record is 14 years old and stands at 200-7x. Something must be different about the way the matches are held if 250s are a regular occurrence in ASSRA matches and 200- 7x is a 14 year old record in the CBA. Time allowed? Reentry? Something else? Not being a wise guy. I just don't know. People are shooting the best of the best equipment wise in the custom classes so there's got to he something else going on when comparing the two.

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RicinYakima posted this 04 August 2018

 Breech seating.

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pat i. posted this 04 August 2018

But people are breech seating in CBA matches too yet the scores sound higher in ASSRA matches. There must be something else.

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Scearcy posted this 04 August 2018

What am I missing here? 200 is the max possible score in a CBA match?????????? 20 shots at 10@ so what does comparing two different games have to do with accuracy?

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pat i. posted this 04 August 2018

I just don't think the max score of 200 at 200 yards are all that common in CBA matches but from what Joe's saying it sounds like the max score of 250 at 200 are commonplace in ASSRA matches. I'm just trying to figure out if we're comparing apples to apples or apples to grape fruits. I find it real hard to believe of all the shooting sports CBA match shooters are the only ones who haven't made real progress in 20 years.

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45 2.1 posted this 04 August 2018

What am I missing here? 200 is the max possible score in a CBA match?????????? 20 shots at 10@ so what does comparing two different games have to do with accuracy?

What are you missing?..... the fact that they use different targets. The targets are from the Scheutzen era and have a center ring that has a value of 25. Ten shots on a score target could get you 250. The rules are different also. They also have group targets and the accuracy requirements are much the same as the CBA has. CBA is not the only shooting sport out there.

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Scearcy posted this 04 August 2018

Exactly! So why are we comparing the two? Different game, different rules, no conclusion to be drawn. I agree with pati that it is very doubtful that the CBA has languished in ignorance while the rest of the worlds shooting sports have continued to progress.

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RicinYakima posted this 04 August 2018

The most recent example is the Military Rifle classes. We started with .22 LR 100 yard target in 2006. By 2011 the scope class winners were determined by X count with 100 points. The new targets SR(?) have an X ring half the size of the old targets and the ten ring is only about 2/3's size. And we still have 100's with high X counts in matches. We have figured out how to make old surplus rifles shoot better than the commercial ones did in the 1980's.

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joeb33050 posted this 04 August 2018

Exactly! So why are we comparing the two? Different game, different rules, no conclusion to be drawn. I agree with pati that it is very doubtful that the CBA has languished in ignorance while the rest of the worlds shooting sports have continued to progress.

We're not comparing the two. The question was about progress in other shooting sports. The only progress I know of is in ASSRA shooting. That's the question. That's my answer. Lurching off into other questions is fine, just don't get us confused.

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joeb33050 posted this 04 August 2018

I just don't think the max score of 200 at 200 yards are all that common in CBA matches but from what Joe's saying it sounds like the max score of 250 at 200 are commonplace in ASSRA matches. I'm just trying to figure out if we're comparing apples to apples or apples to grape fruits. I find it real hard to believe of all the shooting sports CBA match shooters are the only ones who haven't made real progress in 20 years.
We invented hunter class and unl pistol (40 lb) and score went up and group size went down over time. ANY new class will do that, searching for the true average. Left handed plastic stock 23 cal would improve over time. They all flatten out so far. And, some unl/hvy folk went to hunter or pro.
30 years ago  somebody decided that the bullet must fit the throat, and after asking a dozen times I've never had a clear explanation of what that means. And that is touted as the secret of CB shooting.
I've seen NO change in CB recipe for accuracy since the 1957 Lyman manual; and I've looked.

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R. Dupraz posted this 04 August 2018

What does score have to do with anything when trying to determine progress in two different disciplines? Seems to me that it is comparing apples and oranges. And yes, from what I have read, the comparison has been insinuated. Within the context of the present discussion, score's mean nothing. 

Anything other than a comparison of group sizes within like classes and rules between the CBA and the ASSRA or only within the CBA  is wasted effort.

 

R. 

  

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45 2.1 posted this 04 August 2018

30 years ago  somebody decided that the bullet must fit the throat, and after asking a dozen times I've never had a clear explanation of what that means. And that is touted as the secret of CB shooting.
It is, but without some idea of how to do it, you won't be able to. There are several computer programs available that let you draw things on an electronic medium, such as AutoCad. To fit a bullet, or more likely to be able to say a bullet fits the throat, you have to do these things:
1. Take a throat slug of the rifle you intend to fit (with the case attached to the slug). This procedure is outlined in many places on the net.
2. measure that throat slug accurately (to the 10 thousandth with a very accurate micrometer) and plot it electronically in AutoCad. It really works better if you have at least 15 or more measured throat drawings layered over each other to see a particular pattern of fit.
3. Now one can measure an as cast bullet accurately, draw it up and position it correctly on the AutoCad throat drawing. Of course one has to known what influences lack of fit has on accuracy. It is easier to take a very well shooting bullet and plot it against the rifle it shot well in to see exactly how it fits so one can duplicate it (or design something that does shoot well).
My layered drawing had over 30 throat slugs on it from new to well worn rifles. You can see how a throat advances due to wear and erosion and how fit actually occurs. Without that you have to be a parrts changer and see what shoots from experimenting. I'll give you a clue..... most all bullets are undersize, especially in the nose area. Two diameter Barlow type nose riders will only shoot so well (you've basically reached that point without learning more about alloy toughness versus upset). Tapered nose bullets of the correct design (those thirty throat slugs show where the mostly all come together at several points) shoot quite well, better than you realize or can accept as real data. This by itself isn't the total answer.... several other factors are quite important, but you guys simply won't go there.

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joeb33050 posted this 04 August 2018

What does score have to do with anything when trying to determine progress in two different disciplines? Seems to me that it is comparing apples and oranges. And yes, from what I have read, the comparison has been insinuated. Within the context of the present discussion, score's mean nothing. 

Anything other than a comparison of group sizes within like classes and rules between the CBA and the ASSRA or only within the CBA  is wasted effort.

 

R.

I’ll try to help out R. Dupraz with this, it seems confusing to the poor fellow.

 

Pat wrote:

 

Joe just as an aside have the groups shot at the Super Shoot improved that much in the last 20 years? I know some of the records are pretty old. Have there been major improvements in ASSRA groups in the last 20 years? Have Rimfire shooters made great strides? High Power? BPCR? Air Guns (probably)? All the other shooting sports?

 

 

 

I responded:

 

All  know about is ASSRA; we were shooting at WNYSS/Alabama NY when Jerry Ventura shot the first 200 yd 250 score, 10 shots with CENTERS in a 1.75 "25". (Surely Frank will correct this.) That was late '80s?

 

Since then 250s are commonly shot. I believe that we/they went from  old ballard/hiwall/Hepburn/stevens bbls to modern-made bbls and the bbl made the difference= lotsa 250s.

 

Now, the ASSRA went for 40 years without a 200 yard 250; Jerry V. shot one in front of many folks, and since then there have been a lotta 250s shot. Some guys shot 2 in one match, Dale Reynolds for one, with a Pac Nor bbl. I think my response is germane to the question.

 

 

 

Then you wrote:

 

What does score have to do with anything when trying to determine progress in two different disciplines? Seems to me that it is comparing apples and oranges. And yes, from what I have read, the comparison has been insinuated. Within the context of the present discussion, score's mean nothing. 

 

Anything other than a comparison of group sizes within like classes and rules between the CBA and the ASSRA or only within the CBA  is wasted effort.

 

 

 

I don’t know whether you’re unable to understand, or merely being antagonistic-I suspect the latter. No matter which, please don’t respond to my posts in the future; I have more3 important things to do than answer your comments.

 

  

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joeb33050 posted this 04 August 2018

30 years ago  somebody decided that the bullet must fit the throat, and after asking a dozen times I've never had a clear explanation of what that means. And that is touted as the secret of CB shooting.
It is, but without some idea of how to do it, you won't be able to. There are several computer programs available that let you draw things on an electronic medium, such as AutoCad. To fit a bullet, or more likely to be able to say a bullet fits the throat, you have to do these things:
1. Take a throat slug of the rifle you intend to fit (with the case attached to the slug). This procedure is outlined in many places on the net.
2. measure that throat slug accurately (to the 10 thousandth with a very accurate micrometer) and plot it electronically in AutoCad. It really works better if you have at least 15 or more measured throat drawings layered over each other to see a particular pattern of fit.
3. Now one can measure an as cast bullet accurately, draw it up and position it correctly on the AutoCad throat drawing. Of course one has to known what influences lack of fit has on accuracy. It is easier to take a very well shooting bullet and plot it against the rifle it shot well in to see exactly how it fits so one can duplicate it (or design something that does shoot well).
My layered drawing had over 30 throat slugs on it from new to well worn rifles. You can see how a throat advances due to wear and erosion and how fit actually occurs. Without that you have to be a parrts changer and see what shoots from experimenting. I'll give you a clue..... most all bullets are undersize, especially in the nose area. Two diameter Barlow type nose riders will only shoot so well (you've basically reached that point without learning more about alloy toughness versus upset). Tapered nose bullets of the correct design (those thirty throat slugs show where the mostly all come together at several points) shoot quite well, better than you realize or can accept as real data. This by itself isn't the total answer.... several other factors are quite important, but you guys simply won't go there.
They do come out of the woodwork.
45, I don't need a lot of blather. Go to the SAAMI 308 Win dwg, copy it, identify the throat, draw the bullet that fits the throat. Easy. We're waiting.

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45 2.1 posted this 04 August 2018

Joe, you're Hopeless........................ Frank Marshall, Jr. and many others knew throats wear and advance. A rifles throat doesn't stay in SAAMI condition very long, nor do the tolerances match what they say they do either with all the manufacturers out there. Taking the direction you seem to be going, you're not going to solve much of anything, but Good Luck to you anyway.

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joeb33050 posted this 04 August 2018

Joe, you''re Hopeless........................ Frank Marshall, Jr. and many others knew throats wear and advance. A rifles throat doesn't stay in SAAMI condition very long, nor do the tolerances match what they say they do either with all the manufacturers out there. Taking the direction you seem to be going, you're not going to solve much of anything, but Good Luck to you anyway.

 

45, I just want to know what the throat is, and the bullet dimensions are to make "the bullet fit the throat". If you don't like 308, pick another ctg. Don't be the 67th person in a row to not explain. Should be easy for a wizard like you.

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45 2.1 posted this 04 August 2018

45, I just want to know what the throat is, and the bullet dimensions are to make "the bullet fit the throat". If you don't like 308, pick another ctg. Don't be the 67th person in a row to not explain. Should be easy for a wizard like you.

 

Joe, the lead throat slug dimensions encompass the throat area in the barrel, that is they show the dimensions of the throat....however the manufacturer defined them or the throat wear after shooting it for a while. Your rifle probably doesn't match my rifle or somebody else's rifle, same as fired cases out of one chamber not going in another chamber. The dimensions do allow one to fit/check/design a bullet to that rifle though. If a bullet goes in and doesn't touch the right places, then it is undersize and will perform the 1 MOA to 3 MOA normal groups you see. You asked for WHY?....... it's to get you below the normal "why can't we do better" groups you and others put up.

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joeb33050 posted this 04 August 2018

45, I just want to know what the throat is, and the bullet dimensions are to make "the bullet fit the throat". If you don't like 308, pick another ctg. Don't be the 67th person in a row to not explain. Should be easy for a wizard like you.

 

Joe, the lead throat slug dimensions encompass the throat area in the barrel, that is they show the dimensions of the throat....however the manufacturer defined them or the throat wear after shooting it for a while. Your rifle probably doesn't match my rifle or somebody else's rifle, same as fired cases out of one chamber not going in another chamber. The dimensions do allow one to fit/check/design a bullet to that rifle though. If a bullet goes in and doesn't touch the right places, then it is undersize and will perform the 1 MOA to 3 MOA normal groups you see. You asked for WHY?....... it's to get you below the normal "why can't we do better" groups you and others put up.

 

You elusive rascal, you don't know, do you?

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pat i. posted this 04 August 2018

LOL!!!

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45 2.1 posted this 04 August 2018

What fits the throat, how to fit a bullet to the throat or what a throat is? I do know the first two quite well........ and have some bullet designs made by MP Molds that some people rave over. There are enough different illustrations of what things ahead of the chamber are called to confuse most anyone. I for one don't care what you call those items..... I only care about accuracy and performance. You haven't believed the easier to do stuff yet, so the more advanced stuff is out of your comprehension. Let's just leave it at that!

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joeb33050 posted this 05 August 2018

What fits the throat, how to fit a bullet to the throat or what a throat is? I do know the first two quite well........ and have some bullet designs made by MP Molds that some people rave over. There are enough different illustrations of what things ahead of the chamber are called to confuse most anyone. I for one don't care what you call those items..... I only care about accuracy and performance. You haven't believed the easier to do stuff yet, so the more advanced stuff is out of your comprehension. Let's just leave it at that!

 

You're now officially the 67th person in a row who can't explain/draw "The bullet must fit the throat.". What's that buzzing? Is it my BS detector?

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Ed Harris posted this 21 August 2018

This bullet is cut by Accurate to fit a pound cast of a No.4 Mk1* .303 Long Branch Enfield.

I ordered the mold at +0.002 from this print, because my rifle is .316+ and the resulting bullets "fit" mine, not marking the bullet in chambering, but obviously squeezing the coating of Lee Liquid Alox off to show a shiny bullet where the lube was.

 

 

73 de KE4SKY In Home Mix We Trust From the Home of Ed's Red in "Almost Heaven" West Virginia

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Ross Smith posted this 22 August 2018

Okay ya'll: This is half question and half observation. It seems that with jacketed bullets the faster the twist the heavier(longer) the bullet will stabilize. The slower twist, the lighter the bullet. Now, in the cast world, slow twist is best for heavier bullets????????

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pat i. posted this 22 August 2018

Cast works just like jacketed. Slow twist shorter bullet. I saw you ordered a 14 twist Douglas barrel. I always had good luck with the RCBS 165 Sil in a 1 1/2 degree included angle throat. If I remember right it's 1.020. When I made my taper die I switched to a LBT spitzer the same length as the Sil bullet. I know you're just saying weight as a replacement for length but forget all about weight, length is what matters. In fact I've wished for a long time mold manufacturers that don't provide a print would drop weight and replace it with length although RCBS 1.020 Sil doesn't sound as cool.

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Ross Smith posted this 22 August 2018

I was going by advice based on success for the lyman 311299 which is a 200+-gr. have no idea on length. Went thru the same thing on my 32-40 douglas 1-14. The old 165 shoots better than the newer 200grn. Same thing 1" or less.

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pat i. posted this 22 August 2018

I've never tried the 200 gr sil bullet and will be made a liar by someone as soon as I post this but best as my memory serves me I've never heard of anyone who had any luck with that bullet.

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frnkeore posted this 22 August 2018

I've never tried the 200 gr sil bullet and will be made a liar by someone as soon as I post this but best as my memory serves me I've never heard of anyone who had any luck with that bullet.
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I'm not sure what you referencing, regarding the RCBS, 200 gr Sil but, if it's a longer bullet, not not being as accurate as a shorter one. The Egan, MX 4 30 ARD, most likely holds more CBA records than any other. It is 1.25 long w/o the GC and about 1.265 long, with it. It is usually used in a 10 - 11 twist barrel but, will be well stabilized in a 12 twist.
It's also, made with a 1 deg per side taper, on the forward driving band, to match a 1 deg per side throat and uses a .45 long, .301 bore riding nose.
While I can't say that I've seen the 200 gr RCBS win a CBA match, I have seen it place well. It is designed, something like the Egan at 1.175 long w/o GC. It has a tapered forward driving band at a angle of .586, per side, with a much shorter .110 long x .301 bore riding section.
They are both designed with a .309 base band but, many had the base band made on their Egan's at .311 - 314.
The RCBS can be stabilized in a 14 - 13 twist barrel and if the throat for a RCBS were cut at .586 deg, I see no reason that it couldn't preform as well as the Egan.
There is no magic in cast bullets. The magic comes from attention to detail and the bullet fit, to the throat.
Frank

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frnkeore posted this 22 August 2018

I posted the above, in responding to Pat I's post. I had missed this thread, as it started when I was in Spokane, attending a 2 week shoot.

I've read most of it now and will hopefully answer some of the questions.

1. The 25 ring in a ASSRA, 200 yard target is 1.50". Most 250's create a 1 - 1.25" group. Our 5 shot group record is .275 and 10 shot, .924. I have seen 10 shot score groups, in the 7/8 range but, they don't qualify for group records, of course.

2. There are basically three reasons that ASSRA and ISSA scores have improved in the last 15 years. The first is barrel design and quality. Although there have been other barrels that have shot 250's, Douglas and Pac-Nor being two, the RKS, choked, gain twist, far exceeds them. BTW, Dale Reynolds, shot four 250's and one 249 (1249/1250) in a ISSA , 50 shot match, with a Pac-Nor barrel but, neither he or no one else has matched or exceed it but, there are a lot of ISSA, 50 shot scores in the 1240 - 1245 range at the annual match at Raton, NM.

1. Barrel

2. Shooter skill and attention to detail and wind reading ability

3. Breech seated bullet design

Our bullets won't help CBA fixed ammo guys improve their scores though.

To answer JoeB's, bullet fit question. The taper of the bullet, usually on the front driving band or bands, must fit the taper of the throat and if it has a bore riding portion, it must contact the lands of the rifling as a basic start. It will help, if the base band fits any freebore that the chamber has, while still being in contact with the ID of the case mouth and that case mouth be chamber size on the OD, to to guide the bullet to battery.

Frank

 

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pat i. posted this 22 August 2018

Were talking about a 14 twist barrel and have you or anyone you know shot the 200 sil bullet?

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Larry Gibson posted this 22 August 2018

Not the RCBS Sil Bullet but I have some experience with the 311299 in my 14" Palma rifle.  Didn't do a lot of load development with it but did determine that it will stabilize fine in the 14" twist. 

LMG

Concealment is not cover.........

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pat i. posted this 22 August 2018

Stability doesn't guarentee accuracy.

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frnkeore posted this 22 August 2018

Pat,

Since the RCBS is a GC bullet, I can't shoot it in competition but, I have shot the NEI 168 308 PB (2 bands and a long bore riding nose) that is 1.19 long in my 14 twist Douglas barrel. I have shot 1 1/4, five shot groups with it @ 200 yds. I believe that shows it's stable and accurate. The bullet that I shot the most, before going to my 33 cal rifle, is a tapered, .310 - .305, spitzer bullet that is 1.165 long.

Starting in June, I have now gone back to 30 cal, 13 twist barrel and have started shooting a bullet 1.30 long, that is accurate. I got 2nd place at my Spokane match with it. It tips slightly but, I will shorten the base band by .025 and that will stop that. I've got a lot more development work to do on this rifle but, it's starting to produce results.

I've been shooting in ASSRA competition, since 1985 and I always shoot the longest bullet, that will stabilize in the twist rate that I use. Some people in my discipline, shoot over stabilized bullets and do well but, I think that any RPM, over what it takes to stabilize a bullet, is wasted.

Frank

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pat i. posted this 22 August 2018

Frank so you haven't shot the RCBS 200 Sil. I haven't either but was just passing along what I've heard and read. Maybe it had nothing to do with the design itself but with the dimensions the mold cast.

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Larry Gibson posted this 22 August 2018

"Stability doesn't guarentee accuracy."

pat

No it doesn't.  As I mentioned my testing was limited.  The testing was done with one powder pushing it hard as I was asked; how it would do in the 2400 = 2500 fps range.  I quickly found it was fine for "hunting accuracy" giving 1 1/2 - 2 moa accuracy in that velocity range with the one powder.  The person I ran the test for was satisfied with that so I didn't test any further as I had no intention of using it for any CBA competition as the 311466 and 30 XCB were proving excellent in my Palma rifle. 

Apparently competition accuracy is your interest?  Only way you'll know if it meets your "accuracy" requirements is to try it?  Be interesting to see the results. 

LMG

Concealment is not cover.........

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pat i. posted this 22 August 2018

Larry I'm chasing pb bullets in fixed ammo and smooth bore trade guns in muzzleloaders at the moment so will probably never get around to testing the 311299.I don't even own the mold and have no interest in getting one.

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