gas checks

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  • Last Post 09 December 2007
[email protected] posted this 07 April 2007

i'm having trouble with final fit. after seating a 180 grain win 308 (309) bullet it isn't holding o.a.l. using a lee neck die which seems to b compatiable with the bullet. problem seems to be the gas check which outside diameter is .314. the gas check seems to be spreading the case mouth to the point when seating the bullet isn't being held. i tried using a minimum crimp but the gun (savage model 10) doesn't like it. alloy is about 50/50 w.w. and lineotpye. would heat treating and not using a check get me there?

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CB posted this 07 April 2007

How are you crimping the gas check onto the bullet? What type of gas check are you using, Hornaday or Lyman? How are you sizing the bullet and to what diameter are you sizing it to?

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CB posted this 07 April 2007

Are you using a .314 H&I or Lee push through die to seat and size the check? Loading a 308 is a pretty easy thing to do so you'll have to explain a little more as to what you're doing. If the bullet casts at .309 use a .309 or .310 sizer to seat/size the check and lube it and everything should work alright.

Pat

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[email protected] posted this 07 April 2007

the gas checks are Hornaday 30 cal and they have been put on by Lee sizer-lub (.309). the funny thing is that I tried not sizing them, just gas checking them on a Lyman lub-sizer and still don't have a fit. out of the mould their micing .311. question I have is should a 30 cal. gas check mic .314? I use the same check for a SKS but I'm sizing the 160 grain bullet to .313 so there is no problem. I want to thank you guys for your replies. charlie

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[email protected] posted this 07 April 2007

you people got me thinking. why would a bullet come out sized at anything but .309 out of a .309 sizer? the bullet is fine but the gas check wasn't. I miced them again at the check and then resized. now theyr'e micing .308 which is another issue. why not .309? why not .308 the first time? I hope I don't have to resize twice everytime. maybe it's time to go back to lyman and get their sizer and top punch. this is the first time resizing with Lee's. thanks again, charlie

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CB posted this 07 April 2007

Ahhhhh! You are using a Lee push through die set up. I got a couple of those. I use them to get bullets that come out of the mould a little large back down to size. Let me explain. If you don't get a mould to close properly or all of the way, you will end up with a bullet that is a bit large.

If I were you, I would get the proper size Lyman sizing die and one of their gas check seaters which is a little u- shaped tube looking thing that goes in the Lyman Luberisizer that stops you from going full stroke and crimps on the gas check. Then after you get all of the bullets gas checked you remove that little jobiedoa nd size and lube the bullet and it should come out a the size of the sizing die.

That should save you from sizing them twice.

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Minnesota AL posted this 17 November 2007

I'm new here, searched a little on gas check sizes and found this thread.

I'll be trying gas check cast bullets for the first time. I have a lot of experience with plain base bullets in BPCR, but I want to cast my own bullets for smokeless use in a 30-40 Krag. The gun leaded terrible with 309 gas check bullets from a commercial caster ( I had to use a Lyman Foul Out for most of the day and removed lead like I've never seen before). I'm trying some 310 bullets but it looks like leading is starting again after less than 50 rounds. Loads were I recall 20 gr of SR4759

I've never had good luck keeping a bore lead free with hard cast bullets (handguns). Meanwhile, I've never gotten lead out of a gun using black powder after 1000's of rounds.

The Krag barrel groove slugs at something like .3093-5 so I figure size to .310

Question, are all 308 gas checks the same size? From this thread it looks like they are all oversize and I size them with the bullet. I have the Lyman 450.

I'm going to try wheel weight alloy and go to a light charge of Unique (1200 fps)

Al

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AMMOe posted this 17 November 2007

You might want to consider a larger bullet diameter than .310 inches. I shoot a few Krags and, with the exception of one that was rebarreled with a Douglas barrel, all like .311 thru .313” bullets best. As you are probably aware, make sure all the copper fouling is out of your barrel.~Andy

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CB posted this 17 November 2007

Al,

Whatever the bore slugs at is fine, but you need to slug just the throat or chamber-cast it to find the diameter of the start of your throat. If it's worn out to a diameter of say .312, you will get gas flashing lead in that .002” slot around the circumference of the .310” base. So size your base to the throat at .312” or whatever so it seals first.

20gr of SR4759 is just a little stiff. My partner and I use 18gr in our 30-06s and in my Krag with that as our 'accurate' load. The west coast guys like 16gr of Alliant 2400 (not older Hercules) in their 06s, but that'd be close to working in your Krag also.

I fought fouling, not necessarily lead, but fouling and lead flakes for 3 years in my 308. Last year I finally got a good fit with the base in the opening of the throat and now I hardly clean. My rifles for CBA military matches also have cleaned up a lot because of a better fit at the opening of the throat and the base............good luck.....Dan

 

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Minnesota AL posted this 17 November 2007

Thanks guys,

I slugged the bore about 6” in from the muzzle so I'll go try the chamber end.

The mold I bought is a Saeco 4 cavity 30 caliber, about 195 gr. (NIB with handles for $79 shipped, I couln't pass that up). I haven't cast a bullet yet but may get to it this weekend. If the bullet is .312 I can try some as cast, depending on what I see for a chamber slug. I have some cerrosafe but have never used the stuff as driving a 32 cal lead ball into a bore sure seems easier.

Al

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454PB posted this 17 November 2007

The gas check seating method I use with the Lee dies is to apply the check to the base, position it in the die bottom, them give it a light “smack” with the punch. Once seated, push it on through. This seats the check squarely the same way the Lyman check seater does.

If your Lee die is producing a .308” bullet and it's stamped .309", it is defective. It can be returned to Lee or easily honed out another .001” using some fine emery and crocus cloth on a wood dowel.

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Minnesota AL posted this 02 December 2007

Looks like I can skip sizing bullets for the Krag. A cerrosafe cast is showing a minimum of .314 in the throat area. Lot of ram rod wear on this rifle, very visible at the muzzle, looks like we have some in the chamber throat too. In one direction the throat is closer to .319". These are from a cerrosafe cast.

My bullets are casting at .312-.313 with wheel weights.

Al

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CB posted this 02 December 2007

Al,

You may still get decent accuracy leaving the base unsized and crimping on the gas check at .314, using the low/medium velocity loads with a medium hard alloy like #2 Alloy. My krag and 03-A3 are both the same as yours and they shoot good. The Lyman 314299 works good in the old war dogs. Don't give up on the Krag, I believe shooting CBs in the old bores is their best chance at shooting well again and to enjoy many hours shooting the fine rifles, not just looking at them...................Dan

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billwnr posted this 02 December 2007

[email protected] wrote: i'm having trouble with final fit. after seating a 180 grain win 308 (309) bullet it isn't holding o.a.l. using a lee neck die which seems to b compatiable with the bullet. problem seems to be the gas check which outside diameter is .314. the gas check seems to be spreading the case mouth to the point when seating the bullet isn't being held. i tried using a minimum crimp but the gun (savage model 10) doesn't like it. alloy is about 50/50 w.w. and lineotpye. would heat treating and not using a check get me there?

I missed your post back in April...but found it now.  I had the same problem with my military .30/06 as the bullets weren't held firmly enough and the bullets would/could push in the cases.  I was using the lee collet neck die.    I have since switched to the Redding bushing die.

In my case it was an aggravation as  it didn't affect accuracy.  You might check things out and see if it affects your accuracy.

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Minnesota AL posted this 02 December 2007

Dan,

Thanks for the encouragement. I plan to keep shooting the Krag. That the muzzle is pear shaped from ram rod wear, doesn't seem to effect the accuracy. I shot this rifle 10 years ago with factory 220 gr jacketed and it shot a great group at 100 yards. Told the owner he's got a buyer when he wants to sell it.

It shoots fine, I use it for an informal military match where we shoot sitting, kneeling, standing at 50 yards. Most guys use light loads. Problem is the amount of leading and the decay of accuracy. I'll try my Saeco 301 mould bullets right out of the mould.

Question, do I need a sizing die to seat the gas checks with a Lyman 450? If not, I could attach the gas check and dip lube the bullet.

Al

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Ken Campbell Iowa posted this 03 December 2007

Hi....    I would consider 2 things ( to start with )

Unless you are collecting that Krag... or shooting under real strict rules:::

I would see if I could find a Krag Doctor in your area, and pull off the barrel, set it back about a neck length ... ( .4??? ) and rechamber it mostly to get a cast bullet throat ....  thus making your life easier (g) ...  most common good bullets ( RCBS Silhouete tpe, Lyman 311290-99 types ... 311284 ... SAECO nose riders ... you lucky dog ... ) will like a short .309 or 0.310 freebore up to about one caliber long, then a 1.5 or 3 degree angled taper down to bore diameter.

THEN I would do a firelap on your barrel, probably that old rifle would appreciate being spruced up a bit.

Because it's the entire length of bore that leads.. rough ... ( probably ) I would suggest the fire lap using mild loads with jacketed bullets ( your 8 grains of Unique would be ok ).... the jacketed bullets having abut 220 or 280 grit rubbed into the jacket between a couple of steel plates ...

usually lead lap bullets are recommended, but there is some evidence that that takes out mostly material closer to the breech ... such as burrs from a fresh chambering (g) .. reamer marks ... and not so much down the tube a bit.  I have never had to use more than 8 lapping shots yet with 280 grit ...  and finer grits have not shown me anything ( maybe a shinier bore, but not better performance ... ) ..

Hope this helps some.. ken campbell, deltawerkes

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AMMOe posted this 04 December 2007

I hate to disagree but I must. Technically, the set back and chamber would be the thing to do but with the price of original, unaltered Krags being what they are today, setting that barrel back could cost him many hundreds of dollars in lost value. Better to just work with what he has and hope for the best, or find a new rifle.

I shoot Krags and haven't bought one in some time. When I mentioned to a Krag shooter that I had two unaltered actions I was flabbergasted at the amount of money I was offered for them. Evidently, the Krags are scarce enough that guys deem it worth while to build up guns from parts. That's a good sign that orginal guns should be left unaltered, I think. ~Andy

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Ken Campbell Iowa posted this 04 December 2007

Hi... we are not so much in disagreement, I did mention don

I suppose I should mention that about a month ago I watched a genuine perfectly functional Krag Carbine go at a farm sale for $200  ....

Someone had hacked on the stock, but the metalwork was just fine ...


To me collecting but not shooting a firearm is like finally getting a date with a knock-out georgous gal, then deciding she is too beautiful to try to give her a squeeze ... 

I grew up shooting ( and cleaning and oiling (g)) Popes, Hi/Low Walls, Stevens 44, 44.5, Krags, Win 73, 92, 95, Neidner Hi Walls ...   shot em all and a lot, too ... ah wasted youth !!! 

Still got some DuPont #80 ...   I guess I did collect something for posterity.  Think I will have it mixed with my ashes and ignited when I go ... or maybe I won

regards, ken campbell, iowa

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Minnesota AL posted this 09 December 2007

I'll try to keep the Krag as issue. I am looking on the web gun auction site for a Krag barrel. Can't see that a proper barrel would hurt the value, especially if I keep the original.

Still need to know about these gas checks, if I'm not sizing the bullets, do I need a sizing die to seat the gas checks on the Lyman 450? I've cast a lot of bullets but I have never cast a gas check bullet. Need some help. Thanks.

Al

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