Making Another Bump Die

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OU812 posted this 17 January 2018

Using my mini lathe I made a nose punch to align and shorten the nose of bullet during bumping. Taper is a strait 40 degrees included angle. This should help prevent nose from slumping when using softer alloys or hard alloys at faster velocity.

Ordered a .224 diameter chucking reamer to cut bump die body so that most all style bullets can be bumped for better alignment. Throat of rifle is cut strait @.2243 diameter for LBT style bullets.

Diameter of aluminum stem is .223, diameter of  steel die body will be .2240

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OU812 posted this 20 January 2018

Notice bearing length of the LBT bullet is longer after bumping. The thicker Gator gas check is perfectly square now. Alloy is about 13-14 bhn magnum birdshot that was age hardened. Filled lube grooves with harder Carnuba Red lube before bumping to prevent collapse of lube groove. I hate using this hard lube (requires heat) and much prefer LBT soft blue.

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Ken Campbell Iowa posted this 21 January 2018

following you all the way ....  my main interest is probably in bullet sizer/swagers/fixers ... seems so common-sense ...

" can't wait " for some targets ... 

which is funny because of course i will wait ...

i think you guys that are putting effort into this casting accuracy thing are going to shame me into getting serious again ...

ken, drowning under huge waves of guilt ...

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OU812 posted this 21 January 2018

Ken,

Couple years ago I cut the throat of my Remington 700 using the hand method...I hope it is cut inline with bore. The bushing on reamer fit snug to bore so maybe it is good.

I will recut my top punch so that bullet tip is slightly more rounded @ edges. after bumping.

BTW this LBT bullet is a verygood AR15 (NATO throat) bullet as cast.

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OU812 posted this 21 January 2018

Bullet measures .2244 diameter after bumping.

 

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mrbill2 posted this 21 January 2018

I guess it just the way it shows up on the picture. To me it looks like the bullet on the right is bent. Kind'a leans to the east.

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OU812 posted this 23 January 2018

mrbill2,

I seated the Gator gas check base first in the RCBS lubesizer, maybe this softer alloy distorted during seating.

I got some more bullets bumped and ready for testing on Friday. Linotype (bottom row) and magnum birdshot alloy(top row) .

 

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OU812 posted this 5 weeks ago

Today I tested this bumped bullet with two powders Tite Group and new IMR4198.  I was very disappointed with accuracy, but will go back and try with different alloy and powder combinations. So far bullet seems fussy with what you feed it. Accuracy ranged from a 1" to 2" @100 yards.

Softer Magnum shot alloy seems to work better than Linotype. Maybe I will try 20/1 alloy next

Tried two different lubes LBT soft and Carnuba Red and could tell no difference in accuracy.

Also shot some jacketed bullets and performance was verygood. So I know the rifle will shoot even with its extra long free bore 

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Ken Campbell Iowa posted this 5 weeks ago

...thanks for the test ....

first the bad news ....  results not according to plan ...

but the good news ::  1) ... the bullets didn't go spinning off into orbit ...as have happened with  some of my good ideas  ......  1.5 to 2 moa is well within my "" works well enough ""  acceptance .... and especially if you never had a real wild flyer......  if you could shoot a 200 shot group into 2 moa you could win a lot of 200 shot group matches ...

and 2) ..we have a learning opportunity ... perfectly consistent and no-void bullets with perfectly seated gas checks are supposed to shoot under moa ( in a under-moa rifle )  ... it would seem ....   so are they getting beat up before they leave the muzzle ?? .... are the harmonics of those loads aiming  the barrel in different directions for every shot ??  .......

i might mention that my beloved 7mm ruger shot 120 mj bullets into 3/4 moa ... but perfect beautiful 163 gr. match mj bullets into 1.5 moa ... with many different load combinations ...still a mystery..   also my 222 would shoot hornady 50 gr sx into 1/2 moa but sierra 50 gr into 1.5 moa ...    all " perfect " bullets .... so maybe some better bullets shoot bigger groups anyway ??  ...

thanks again for the interesting testing.   ken

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OU812 posted this 5 weeks ago

Ken,

Or maybe the factory barrel is not broken in and fowls too easily or quickly with longer bearing surface bullets. I could feel hard fowling about half way down the bore during cleaning.

Harmonics may be another cause? I will try other powders.

BTW   no wild flyers.

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John Alexander posted this 5 weeks ago

I think the wrong powder at the wrong pressure is sometimes the cause of hard fouling,  Did it happen with both powders?  Powder branders get it from different manufacturers over time and a powder that didn't foul may turn into one that does in the next batch coming from a different factory.  5744 is an example that has changed over time.

John

 

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OU812 posted this 5 weeks ago

The new IMR 4198 also smells different than old when burned, I will try the two other versions, older 1996 vintage and new H 4198.

Titegroup did not shoot as accurately as it normally does, and I do not remember if it fowled like the 4198. Will check next time out.

I will try putting a thin coating of lube on bearing surface of bullet to see if accuracy improves and if fowling is reduced. I also might try using less lube (filling gas check shank area only)

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John Alexander posted this 4 weeks ago

Let us know it coating the bearing surfaces has any effect.  It seems so reasonable and I used to do it a lot but when tested I couldn't dectect any difference but who knows.

John

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OU812 posted this 4 weeks ago

I was reading the Lee Bullet Sizing Kit instructions and they state "For rifle and hot handgun loads, it is best to re-lube the bullets to insure the sized portion is recoated". So after seating bullets I scuffed bullets with 0000 steel wool and then put a thin coat of liquid alox on the long bearing surface. Soft LBT blue lube is packed inside gas check shank. 

Also loaded a few using just the soft SPG lube (no alox) thinking this thin lube will work better in cold weather. Bullets were scuffed and hand smeared with thin coat of SPG on bearing surface after seating.

Trying 4759, H4198, n120, 680, Titegroup

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OU812 posted this 4 weeks ago

 Notice rifling marks on bullet (even length all around bullet) after chambering and ejecting. This bullet measures .2252 diameter.  Runout is .001 or less with every bullet seated. SPG black powder lube in groove.

Fouling and wrong pressure curve is the enemy.

These bullets can be chambered from magazine if seated a tad deeper.

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OU812 posted this 4 weeks ago

I will do a chamber cast to try and measure actual shape of throat. I think the first bullets I tried were a tad too small diameter and caused hot gases to blow by and melt lead causing fouling. So a slight taper should work best or maybe cut a larger diameter below lube groove at base of bump die. This should help seal bullet better and prevent blow by.

Or use a softer alloy and bump bullet a tad larger diameter from .2242 to .2252. 

 

 

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Scearcy posted this 3 weeks ago

Good stuff! I am reading every word.

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OU812 posted this 3 weeks ago

I sanded down (steel wool) and reused one of my old pound cast. The soft pure lead bullet was epoxied into case and is holding up well. It can be used over and over to check other 223 rifles.

It is what it is.

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OU812 posted this 3 weeks ago

Had a very good day at the 100 yard range until a double charge of n120 locked my bolt. Hot gases were blown in my face and I thought I blew up the rifle bolt. Case head is just swollen to bolt face and will be removed for another day. The 223 bolt face ring is beefy.

Here are some sub 1/2" groups using H4198 powder, Lino and Hard 15bhn birdshot. The best I could get Titegroup to group was slightly under 1" using 10 bhn birdshot alloy. I know I can do better using Titegroup.

I was mostly shooting just three shot groups trying to find something that shoots good.

I learned again that Lino fouls less than softer Birdshot. The SPG lube, Linotype alloy and H4198 powder did verywell and fouling seemed to be lowest using the soft SPG.

The rifle is a factory Remington 700 VS chambered in 223.

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OU812 posted this 3 weeks ago

I will have to use my Dremel tool to cut case out from bolt face. I feel so stupid. This is the second time doing this.

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Ken Campbell Iowa posted this 3 weeks ago

good news indeed ... looks like you are getting it together with the 223 .

thanks for mentioning the high pressure oopsie ... good to be reminded .... 

a  few years ago i bot on ebay a supposedly good rem 700 magnum bolt body ... but someone had managed to enlarge the ring around the cartridge base .... i am sure the seller hadn't noticed the bulge ... hah ... anyway it would take a lot of pressure to expand that belted magnum solid base and bolt ring ...

more, please ..

ken

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