Loose gas checks.

[Trailboss]

I probably won’t even end up useing my gas checks. I’m useing a soft lead mix at 1200 FPS in a4570 marlin. I notice my checks are a loose fit easily slide on and off with no effort whatsoever.... do I glue them on to hold them in place ?

[charlie b]

Gas checks need to be crimped in place with a sizing die. Sounds like you are not doing that step.

[Wayne Smith]

If your mold is a gas check mold it is likely to shoot better with the check, but no guarantees until you try it in your rifle both ways. If your gas checks are the old Lyman design they do not crimp, if they are modern they should crimp on when the boolit is sized as Charlie mentioned. Soft lead (pure?) has to fit to not leave unpleasant deposits in your barrel. That's actually true of any boolit, but particularly true the softer the metal is.

You also need to look at your lube - do you get a lube star at your muzzle after shooting? That's one way to determine the adequacy of one's lube. No lube star means your lube is either too hard or running out before the boolit gets to the end of the barrel. Unpleasant lead deposits toward the muzzle end of the barrel means the same thing.

You are right, at 1200fps gas checks are not necessary unless your boolit loses accuracy without them. Yes, it is a little complicated, but that's part of the fun.

[JonB_in_Glencoe]

Trailboss,
Welcome to the forum.

I am gonna assume you are doing everything correctly. If that is the case, then the only thing left is the size of the shank (boolit base) is undersized...and this is a fairly common problem.

One trick is to size the boolit without a GC, then install the GC and size the boolit again.

The first sizing can enlarge the shank, making a better and more snug fit for the GC.

[oley55]

One trick is to size the boolit without a GC, then install the GC and size the boolit again.

The first sizing can enlarge the shank, making a better and more snug fit for the GC.

good info, I need to store that away for future recall.

[Soundguy]

What alloy are you using?

What weight bullet?

Are you sizing?

[gwpercle]

My gas checks are crimped on when sized .
Lyman 450 lube/sizer , one cycle of the handle ...check is crimped onto boolit , sized , lubricated and ready to load .
Try shooting softish alloy boolit in a Marlin Micro-groove rifling with a gas check installed ...
you just might see a nice improvement over unchecked boolits .
Gary

[GregLaROCHE]

Non checked GC boolits work fine in my .45/70 Marlin for plinking. I PC most of mine now, but even before I started PCing, they worked well at lower velocities.

[Trailboss]

I’m useing 98 roof flashing lead bought new from hardware and 2 per cent tin bought from proper shop. CBE mould 4570 To be shot at 1200 FPS 405 grain mould but they always seem to be 412 with my mix ...I’m not sizeing at this stage. I’ll try first to see how they shoot. And I’ll get into slugging my bore and sizeing if I need to improve accuracy

[mehavey]

If you're not sizing, there's no way the gas check can crimp itself to the shank.
I recommend at 0.460 lee push-through sizer for that reason -- if not for just plain uniformity.

[frkelly74]

I have resorted to super glue once to secure the gas check to some 6.5 boolits. I am going to shoot them sometime and see how they worked.

[Soundguy]

agreed.. if you are not sizing.. I would not have chosen gas checks.. not sure I would be shooting super soft lead and no gas checks at much over 1000 fps

[Burnt Fingers]

agreed.. if you are not sizing.. I would not have chosen gas checks.. not sure I would be shooting super soft lead and no gas checks at much over 1000 fps

You must not shoot much 22 LR.

[JonB_in_Glencoe]

I’m useing 98 roof flashing lead bought new from hardware and 2 per cent tin bought from proper shop. CBE mould 4570 To be shot at 1200 FPS 405 grain mould but they always seem to be 412 with my mix ...I’m not sizeing at this stage. I’ll try first to see how they shoot. And I’ll get into slugging my bore and sizeing if I need to improve accuracy
I highly recommend you size your boolits.

On rare occasion, I will load some unsized boolits (TL'd) for pistol, but I will always size Rifle boolits.
>>>With that said, I guess some of the Schuetzen shooters will load unsized boolits, but they have custom molds suited for their rifles...and that's a whole different game.

[mehavey]

45-70 / 405gr / 1,250fps is OK for base-base/30-1 bullets.
Shooting a bare-base that's otherwise designed w/ a gas-check shank [may] be OK

[Carbineone]

So I have a 100 or so plain cast lead bullets with a gas check already attatched..I do not crimp much..Are people saying these could separate after firing with no crimp and possibly get lodged in the barrel somehow? Thanks

[mehavey]

No. you are referencing a crimp of the case mouth on the bullet when seated.
We're talking about sizing the bullets long before that, so the gas check crimps on the bullet base

[44Blam]

I have some boolits that have big shanks and the GCs are fairly hard to get on. For those, I have an Irwin clamp that I use to seat the GC. Then for some boolits, I PC first and then the GCs fit. Finally I have others that I PC first, then pass the boolit upside down (wide MPLAT boolits only) through the sizer to crimp the GC.

[Winger Ed.]

The checks are slightly over size.
If they aren't crimped on with the sizer---- that also sets your boolit to the correct diameter,
they might even fall off inside the case.

It's another one of those things that isn't at all like Burger King.
You don't get it your way........... You do it their way, or ya don't get nothing.

[Soundguy]

You must not shoot much 22 LR.
I do..and 22 isn't pure lead.

I have 22 in hand that won't scratch with a fingernail. I have 5-6 bhn lead wire that will. My lee hardness tester shows about 8. Fryxell mentioned at least 2% tin for 22's and that was years ago. With lead bullets trending harder to survive shipping without marring my guess is they're getting a little bit of alloy with something. Tin etc. Perhaps even. Very low % bismuth back in 2015 Winchester experimented with bismuth in 22lr and 357.

[HBAR2989]

I probably won’t even end up useing my gas checks. I’m useing a soft lead mix at 1200 FPS in a4570 marlin. I notice my checks are a loose fit easily slide on and off with no effort whatsoever.... do I glue them on to hold them in place ?

For what it's worth, I have to glue mine on before sizing. I have a Ranch Dog 350 gr mold, and Hornady checks won't stay on even after running through a .460 push through sizer. A dab of super glue works great. Then tumble lube and size.