Hello all, this is my first post on this forum, please be gentle. I have been reloading for awhile, all jacketed bullets. I have just started to use cast bullets. I have an Enfield that mics out to .316 in the grooves. I have found a mould that will be OK. I understand that cast bullets in the 1400-1600FPS range requires a gas check. I think I want the type of gas check that crimps on, but not positive. Heres my dilema: the closest gas check is for a 30 caliber bullet. Not ever seeing a 30 caliber gas check, how would that mate up with a .316 bullet. In other words its probably smaller in diameter than the .316 bullet I plan on using. I chose the crimp on style for fear that the press on type would fall off the bullet when seated in the cartridge. I guess my 3 questions are, #1, do I need to use a gas check in the 1400-1600 FPS range. #2, do I use the 30 caliber crimp on or press on gas checks. #3, will the 30 caliber gas checks present a problem with a .316 bullet? Many thanks in advance for your responses. Uncrichie...

The O.D. of a Hornady 30 caliber check is 0.319" - 0.320", so it is plenty big enough for your situation providing your mold is cut for a 30 caliber check, and it probably is.

32 caliber checks and 30 caliber checks are not interchangeable because they require different shank diameters. A 30 caliber shank is about 0.285" while a 32 caliber shank is about 0.301". If your mold is cut for 30 caliber checks then use a Hornady 30 caliber check. If the mold is cut for 32/8mm caliber checks then use Hornady 32 caliber checks.

Yes, use Hornady checks, not Lyman. The Hornady checks fit better and cost less.

Gas checks are not required in a rifle at 1600 fps. However, I would recommend a gas check bullet just because it is more forgiving in many ways.

I don't know if you need a gas check or not. Probably you'll just have to shoot some. I just did that with a little 120 gr 30 cal Lee bullet. I've always shot them in real soft loads, so I never made much distinction. If I was going to shoot them right away they often went bare, but if they might stay around for awhile I put a CG on so the lube was kind of separated from the powder.

The other day I shot some both ways, and to my surprise, the bullets with GCs shot a lot better. I therorize that the GC increases the bearing length on this short bullet,and it shoots better for that reason.

The heel for the gas check mikes about .285-.289 on one of my 30 bullets. So if the heel on your bullet is similar, the 30 GC should fit. The largest outside dia of a Hornaday 30 cal GC is .319. This is the brand that crimps, so I would say it could be run through your sizer and still come out large enough to ride your bore. I would say for this reason you should use the Hornaday GC. The Lyman GC may not be thick enough to fill the gap.

I've found that gas checked bullets are more accurate then the plain base. My theory is that the gas check provides a more uniform base for the gases to work on when the bullet leaves the muzzle.
A suggestion: Anneal the gas checks prior to using. It's real simple just throw them into a pan/skillet put the pan/skillet on the stove and heat them until they change color. If you have black ashes mixed in with the gas checks and the checks themselves look like they went thru a fire you're right on the money. Copper alloys tend to work harden in the manufacturing process, the result is spring back after crimping.
What is the diameter of your sizing die?
Jim

Thanks for the rapid replys. The info provided is exactly what I needed. Once I cast some bullets with this particular mould I'll have a better handle on the base diameter for the GC. Reference to the Sizing die diameter, I'll have to wait to see the exact size of the bullet in the alloy I choose. I'll probably have a friend ream a .309 die and have a new pin turned to fit. Thanks for reminding me of my next question. Is there anyone who offers sizing dies for the Lyman lubrisizer in oddball sizes such as .316??? Thanks again for all the info. Uncrichie...

Only thing I haven't seen and could add would be to use a gas check if the mould is cut for one.

You can get some leading, even at low velocities, using a GC design without the GC.

uncrichie:
In the past, when I shot cast bullets, it was pointed out to me that my GC's were coming off. They were Hornaday's & I thought they were crimped on just fine. Guess I was doing something wrong but I don't know what. At any rate, my gunsmith noticed what was happening & he suggested that I put just a dab of super glue on the check before seating. I tried it & had no more problems. Just an idea for you to consider. Good luck, Bear in Fairbanks

For those of you out there who use traditional copper crimped on gas checks, I have a product that willl take care of all of the frustrations you have had in the past with your gas checks.
My solution?
SOFT Gas Checks.
They are a product that I sell in my store, and boy, lemme tell you, they are the best thing ever invented for lead bullets.
Basically, before you seat your bullets, you cookie-cutter the wax over the case mouth and seat the bullet into it. It will not melt and run down into your powder or anything like that, so it does not affect the performance of your loads.
The biggest success that I have had using this product is with one of my personal rifles.
I have a 300 H&H rifle which I used some old hard-cast UNLUBED (totally dry!) lead bullets, and these SOFT gas checks.
When I took out the rifle, it was already dirty and had not been cleaned in a couple of years.
I shot 5 rounds at a time and at the end of about 20 shots I looked down the bore and guess what I saw.
NOTHING!
The gun actually looked like I had just swabbed it with solvent and was CLEANER than when I left home with it.
I would highly suggest trying these, especially if you are using a bullet diameter for which there is not a gas check specifically made for it.

Check out SOFT GAS CHECKS on my website.
www.cliffsgunsmithing.com

-Spencer

I think you will NOT need gas-checks on a bullet up to perhaps 1400 FPS if the bullet alloy is hard enough. But a gascheck SHOULD be used on bullets that have a shank designed for a gas-check. In other words, use one if the bullet is designed to have one. If you want to shoot a bare-based bullet, you should use one that has a full diameter plain base. In addition, it is best to use a bullet that is slightly over groove diameter when shooting cast bullets - in your case, a .317" or even .318" bullet. The reason for this is to try to prevent as much gas blow-by as you can, because gas blow-by damages bullet bases and bearing surfaces. This is what ruins cast-bullet accuracy and increases the tendency for leading.

Hi there, shopcartracing:



Sounds interesting, but I've wondered how these soft gas checks do when the base of the bullet is below the case neck?



Wouldn't the soft gas check drop down into the powder unless it was a compressed load? I can't imagine that they are so sticky that they adhere to the base of the bullet throughout the handling of loaded ammo...



I can see that these soft gas checks seem perfect if your bullet base is in the case neck, and particularly if your powder charge fills the case to keep it there.



Your price seems resonable, so I await a report on how these soft gas checks might do in my .358 Norma Mag where the bullet base is below the case neck!



jpb

I saw your post and registered just to respond to it.

I've spent quite a bit of time casting and shooting cast bullets through Lee Enfields. As you've noticed, their barrels have groove diameters which are a bit on the large size. To cut to the chase,..

I found that the oversize barrels on the Enfields were perfect for shooting .308 diameter bullets which were patched with,.. get this,.. teflon tape! The RCBS 30-180FN is the perfect bullet for this endeavor due to it's long bearing surface and multiple lube grooves. I cast the bullets from quenched WW alloy. I ran my pot hot,.. about 750 degrees and timed the cutting of the sprue so that the bullets were just solid enough that the cutting wouldn't tear a hole in the base. Then I'd knock them from the mold directly into a 5 gallon bucket of water. After 24 hours, they'll go about 23 BNH,... pretty dad burn hard. I didn't size the bullets. I just used my sizer to crimp on the gas checks. After the gas checks were crimped on, I'd tightly wrap 5 rounds of teflon tape around the bearing surface of the bullet. If you wrap it tightly, it'll stay on very well.

The patched bullets must be loaded into the cases with a little bit of care. It's best to give the case mouth a slight flare before seating the bullet. Seat the bullet just as deep as the neck,... don't allow it to extend into the body of the case,.. then close the flare flush against the bullet with a .30 cal. taper crimp die.

I used slow powders (H4350 was my favorite) and could push the hard teflon patched bullets to 2000 fps with absolutely no leading whatsoever. My rifle would group them into 3" at 100 yards.

I've tried many cast bullet combinations in rifles, and I never had as much succes as I did with this recipe. The Enfields are perfect for teflon tape patched .308 bullets,.. and it's as if the RCBS 30-180FN was custom designed for such.

If you're a guy who likes to tinker (and most cast ballers are) you're going to have fun with this.

There's a thread in the "Bullet Making" forum about paper patching jacketed bullets.