Cast (Rifle) Bullets - Gas Check or Not

[bluemike807]

Im branching out into casting for my Lee Enfield No4 Mk1 and Mosin Nagant. After I slugged both barrels, I found they each prefer .312 sized bullets - I've got my eye on a mold, but am unsure if I should pursue something compatible with gas checks.

Would appreciate folks' perspectives.

 

[Canuck44]

Im branching out into casting for my Lee Enfield No4 Mk1 and Mosin Nagant. After I slugged both barrels, I found they each prefer .312 sized bullets - I've got my eye on a mold, but am unsure if I should pursue something compatible with gas checks.

Would appreciate folks' perspectives.

I shot cast out of my #4 & #5 rifle. Using gas checks allows you to maximize the benefit of cast boolits. I use water quenched boolits cast from WW alloy. Using gas checks I have run loads out to 2100 fps without any leading. All the gas check does is protects the base of the bullet and prevents gas cutting which is the major source of leading when shooting lead bullets.

If you intend to pursue casting for the .303 use a gas checked boolit.

You might want to consider joining this forum:

http://castboolits.gunloads.com/

The guys there are quite helpful to new casters and there is a wealth of information there pertaining to shooting cast boolits out of the .303 Brit.

Take Care

Bob

 

[Old Ranger]

I own several 30 cal moulds and have shot thousands of cast bullets out of numerous military rifles including 5 303's and 3 MN's. My best success with the 303's and 7.62x54's has been with Lyman 311299 (with gas check ) sized to correct dia.

 

[H4831]

This poll is meaningless and too ambiguous to answer. There is no one answer, it depends largely on how fast you are driving the bullets, whether or not you need a gas check.

 

[phishroy]

This poll is meaningless and too ambiguous to answer. There is no one answer, it depends largely on how fast you are driving the bullets, whether or not you need a gas check.

x2

also if using a gas check mold it is better to apply gas checks to those bullets. many people tried shooting gas check bullets without gas checks and found out the hard way that it does not work well.

use gas check bullets for higher pressure/velocity

use none gas check bullets(flat base or bevel base) for lower pressure/ velocity.

my 2 cents

 

[mikeystew]

For me, in a .303 i would use a gas check.
With a water quenched bullet, a gas check and the proper lube and number/size/shape of lube grooves, you could easily reach jacketed velocity with minimal leading if the bullet fit is correct.

The really important and often mis-understood function of a gas check is to prevent the grooves formed in the bullet from widening when it slams into the rifling at high speed, which forms a void on the leading edge of the grooves in the bullet on the far side of the lands allowing the gas to escape around the bullet... if that makes sense. the copper base will grip the lands better than lead alloy and it won't widen at the rifling marks, preventing the gas from slipping up around the boolit. This is the same logic behind why you should use water quenched hardcast bullets that are sized .001"-.002" over groove diameter for high speed loads.

in a nutshell, over 1400-1500fps... generally speaking, you want to use a gascheck. much over 2000fps and you need to use an appropriate high speed lube which is usually a little harder.
Does your bullet design (in mind) use tuble lube or stick?

 

[Canuck44]

I own several 30 cal moulds and have shot thousands of cast bullets out of numerous military rifles including 5 303's and 3 MN's. My best success with the 303's and 7.62x54's has been with Lyman 311299 (with gas check ) sized to correct dia.

Just to add Lyman makes the identical bullet in 314299. I size my boolits .314 and have had excellent results out to 100 yards shooting from a bench and using a scope.

Take Care

Bob

 

[Old Ranger]

Just to clarify the Lyman 311299 vs 314299 mould thing. I have two 311299 moulds. One is SC Ideal (which is old!) and the other an early production Lyman DC. Both cast at .315 and I size to .314 for most of my 303's. Lyman now produces the two different moulds with 311299 obviously casting the smaller bullets. As I have neither of the new moulds I don't know what they cast at.(and individual moulds do vary somewhat) For 303's the 314299 would be the correct choice and could certainly be sized down to fit most MN bores. The "new" 311299 I believe was designed to be used in 308 bores.

 

[Canuck44]

Just to clarify the Lyman 311299 vs 314299 mould thing. I have two 311299 moulds. One is SC Ideal (which is old!) and the other an early production Lyman DC. Both cast at .315 and I size to .314 for most of my 303's. Lyman now produces the two different moulds with 311299 obviously casting the smaller bullets. As I have neither of the new moulds I don't know what they cast at.(and individual moulds do vary somewhat) For 303's the 314299 would be the correct choice and could certainly be sized down to fit most MN bores. The "new" 311299 I believe was designed to be used in 308 bores.

I bought the 2nd mold thinking it would cast smaller diameter boolits for my .30-06 I had. It does but not small enough to make a difference. One drops them out at .314 while the other .315 depending on the alloy I use.

Take Care

Bob

 

[SKS50]

I use the Lee CTL312-160-2R mold in three different caliber of rifles 7.62 x 39,54r and my Sav. 99 in 300 Sav. Bullets are cast from plain old WW alloy and water quenched.

I apply one light coat of my Lee Alox/JPW lube mix. bullets are usually dry and non tacky after several hours at normal room temperature,gas checks are applied for the X39 and 54r bullets with a Lee .314 push through sizer so as not to size the bullet any,then another coat of the lube is applied and bullets are ready to load the next day.

for the 300 Sav. I apply the gas check with a Lee .311 push through sizer and lube once more. I use gas checks for all three of these load because even with the lightest load of Alliant 2400 in my Chinese SKS MV run around 1500+ fps.

For my 30-30 pump gun I use the Lee C309-170-F cast for same alloy as above bullets drop at .311 dia. for my small game and plinking loads I just TL twice and use no gas check MV is around 1200+ fps. with 7 grs. of Red Dot accuracy is around 1" 10 shots at 50 Yds. for large game hunting loads I use the gas check and apply it with the Lee .311 sizer.

 

[ben hunchak]

I use about 10 different .30 cal. bullets in 4 different calibers from 1700 fps to 2800fps and use a gas check on all of them except for the paper patch bullets. I wouldn't bother shooting any of these bullets without a gas check, all are cut for the GC and I'm pretty certain accuracy will be best with the check.

 

[SKS50]

Average group I shoot in my Sav. 30-30 pump gun at 50 Yds. with irons using the Lee 170 gr. RNFP without the gas check applied.