How firmly attached should gas checks be?

[ell198679]

Ive noticed that while some of my gas checks are on rather firmly, and I am unable to remove them with my finger nail. I noticed that on my 7.62x39 cast boolits that the gas check can be removed with some fairly moderate pressure from my finger nail. Is this okay?? Are they supposed to be on really tight?

[Pb2au]

For me, I want them on firmly. If you arrive to a situation where like you, you can pop one off with a fingernail, a tiny drop of super glue inside the cup will help nail it down.
Are you using factory checks or homemade? If homemade, you could change to a slightly thicker material to tighten the arraignment up.

[shredder]

I want them on tight too. I have not tried the super glue trick but I have noticed one of my moulds throws boolits with slightly undersized heel though they shoot well enough. I imagine 20-30,000 psi coming out of the case mouth should shove the check on pretty firmly!

[USAFrox]

You can also scribe your mould where the gas check seats. This will give tiny "ribs" of extra lead which will tighten up your gas check. Use a light touch and creep up on your preferred depth of scribe mark to make the appropriate amount of "rib".

[ShooterAZ]

They should be snug. I have a couple of molds that don't seat as tight as I'd like. Annealing the checks thus making them softer helped make them seat better. This was for a copper check, not aluminum.

[Wayne Smith]

It is a matter of taste. The old Lyman gas checks did not crimp on and people used them for years that way. As long as they don't fall off in the cartridge I don't think it makes any difference. Once the boolit has left the muzzle of the gun the GC has done it's job. If it falls off without disturbing the balance of the boolit - and that is the question debated for years without firm resolution - then it doesn't matter to the terminal ballistics of the boolit.

[Bullshop]

They get a bit more crimp than a sizing die will apply when they pass through the barrel. Your sizer die is crimping to groove diameter or a couple thousandths over as is normally done but your barrel is crimping to bore diameter which can be anywhere from .004" to .008" smaller than groove diameter.
During the passage they are being held firmly against the boolit base by thousands of pounds of pressure.

[Pb2au]

The single biggest reason I want them firmly on there is so that they behave themselves while I am loading the ammo.
Bullshop nailed it. There is a quite a bit of force on them as they travel down the barrel. A couple of pounds at least.

[madsenshooter]

Cute pic there Pb2au! I remember the kitten I once had coming up out of the basement and looking like it had a beard. The beard was the rear end of a chipmunk. Made me mad at the time cause I'd been toying with the chipmunk, nailing chestnuts to a board too big for it to pack off, and watching it out the patio window. Frustrated the little critter something awful!

[milrifle]

I am fairly inexperienced compared to the average poster here, so take what I say with a grain of salt. I bought some .30 cal aluminum gas checks off e-bay when I could not find any Hornady's. My accuracy went south fast. I had 'flyers' out the wazu. You could pull every one of them off with a fingernail. I suspect they were coming off in flight, thereby upsetting the trajectory as they did. Can I prove it? No. Did I try superglue or annealing them? No. Hornady copper gas checks crimp on tightly and I cannot get them off. I have filed a bullet half way through so you could see it in cross section. The ridge around the inner part of the gas check was seated deeply into the lead of the gas check shank. Once I found more Hornady's, I quit with the aluminum checks and my accuracy greatly improved. Well, at least back to where it was before. :grin:

I went looking for a bullet to load yesterday that I had not shot in a while. All I could find was ones with the aluminum check. I pulled them off with my fingernail and seated some Hornady's in their place. I just couldn't make myself go down that road again.

[Wayne Smith]

If you need checks PM Blammer here on this site.

[Three-Fifty-Seven]

I like them tight, so I can't get them off with my finger nail ... Before I load them.

Both copper an aluminum ... On NOE 314129's

http://i153.photobucket.com/albums/s220/ShawnTVT/Guns/762X39First1.jpg (http://s153.photobucket.com/user/ShawnTVT/media/Guns/762X39First1.jpg.html)

These were shot into sand ... At different speeds ...


http://i153.photobucket.com/albums/s220/ShawnTVT/Guns/314129GasChecks.jpg (http://s153.photobucket.com/user/ShawnTVT/media/Guns/314129GasChecks.jpg.html)