Home Forums Reloading Bullet Casting Gas checks needed when powder coating?

I am pretty new to bullet casting. I did it decades ago with a brother-in-law for his black powder pistol. But even that was only round ball.
So I've got some lead, a Lee production pot to cast, a large pan and a propane burner. I also bought a used 450 LubSizer from a guy. Then I heard about powder coating. But it looks like powder coat may be less messy and less BS. Also higher velocities I hope? Looking to do the usual 9mm, 38, 41, 44, 45 pistol but also looking to do 223, 6.5 creedmore, and 30/30 rifle bullets also. So the question is multi prong. So do I need/go to gas check bullets for the low velocity bullets and lube them. Or non-gas checks and PC them? Seems like I'd like to skip a step on the install and expense of gas checks when I can. Now when it comes to the rifle bullets can I just Powder coat them? Any recommendations as to bullet moulds? Or makers of bullet moulds? Lee, Lyman, etc.
Thank you to any and all who take the time to respond.

You can push powder coated bullets to much higher velocities than standard lubed bullets with no leading. But with rifle cartridges you can only get to ~1500? fps before you need a gas check as a general rule (with a lot of exceptions). Also generally....bullets designed for a gas check are more accurate with a gas check installed. After using standard lubes for decades in the last few years I went to using almost all powder coated bullets. Especially for rifle cartridges. It is rapidly taking over.

You need to start reading the Castboolits forums. The easiest way to find an answer is to do a google search of what you want to know and also type in "boolits". They are popular enough so don't need to use a trick to specify a website and the hits from the site will be on top. They have the answer to all of your questions and should have load and bullet recommendations for everything you are reloading.

Thank you!

Just did some testing of SC311-165RF flat base, powder coated and been sitting for about several months. Cast of a range lead alloy I had tested at 0.4 Sn, 1.4 Sb with 1% Sn added. Tested in mo old JC Higgins M51-L 308. Worked up to 1918 fps using Varget and A4350 because those powders are what I have the most stock of. After each change of powder level I lightly cleaned with Ed's Red and found no leading. All groups were under 1 1/4" at 100 yards, with my vision and as long as it's been since I played with rifles I was surprised.
My normal load for this rifle is the NOE clone of the Saeco #315(311-179-FN-15), GC, PC and pushed to 2050. It's taken several deer with no problems.

maybe... you'll have to shoot some to see.

If it is a gas check bullet put it on. It will shoot better.

Yep. Never forget that the bullet's base is its steering end.

Gas checks make a world of difference between cast plain based bullets and those wearing a gas check. In my 45-70 I can only reach 1650fps with the Lyman mold 457193 "405gr" plain base bullet before accuracy begins to deteriorate.

With gas-checked cast lead bullets i have great accuracy and no fouling at 2500fps from a 35 Whelen using Saeco mold #352 245gr GC design. I've fire 3/4" 3-shot groups at 100yds at this speed. This is too fast for use on game, and must be reduced to around 2100fps for hunting to avoid fragmentation. I make my own beeswax based lube and lube my bullets with an old Lyman 450 lube sizer press. This is also necessary to accurately seat gas checks.

I decided the #352 Saeco bullet can be too easily driven to high speeds in the Whelen, so I ordered up the 313gr 35 cal NOE mold double Cavity gas-checked version. Have a JES rebore 35 Whelen with 1:14 twist that should stabilize this down to 1500 fps. Projected launch speed is 2100fps. The mold is still new in the box so I haven't tried it out yet.

A buddy is pushing the Lee 340 grainer estimated to be BHN 15 with PC to 1800+ and change with no leading.

Longest string was over 100 rounds.

After seeing the deer this year I suggested backing off to 1500-1600 fps!
Could NOT eat right up to the bullet hole on them.up

I should hope there'd be no leading at 1800fps PC'ed! (But the same feat can be duplicated with an even softer non-PC'ed GC'ed bullet if careful attention is paid to throat fit.)

I don't care about "eating right up to the hole". While being an admirable attribute I'm more concerned with quick efficient death for a critter - they deserve that from us - and if a bullet (cast or jacketed) delivers that via splatter/fragmentation/utter mayhem then I'm ok with the loss of a couple pounds of bloodshot meat.

Now there's a subject that has tickled the back of my mind a time or two.

I started out using an old Lyman 45 lubesizer and I recall worrying about properly seating gas checks. I went through that for years, then one day while ordering a bunch of stuff I remembered to get a gas check seater. I know I received it, but the next time I was using the 450 on some 410610s I could not find it. Fast forward five or six years...I ordered another one under similar circumstances. I recall receiving THAT one also, and I think I even know where it is. But, the necessity of even having one seems questionable to me. I want to make sure a gas check always stays put and I don't recall ever having had a problem with that, plus I just like for things to look good. Nonetheless, I question the need to worry about seating them perfectly because of the fact that when the round is fired, that gas check is going to be subjected to some 30,000 psi or more. I could be wrong but it seems to me that if that gas check was not seated perfectly when the bullet was built, then it will be by the time the bullet exits a muzzle.

Thoughts?

I agree 100%. Some of my PC bullets shoot better with and some shoot better without.

I don't think so. If the check is seated crooked it'll be pounded crooked too as the bullet parts company with the case and starts up the bore. Think about it, it would have to overcome the frictional lock of the rifling as well as the frictional grip of the check itself, not to mention if it was crimped also like as with a Hornady check. A lot to overcome during the short time it's in the bore. To remove all doubt just make sure your bare bases are square and evenly sharp cornered, and then seat your checks squarely.

Run an experiment with a control group of perfectly checked bullets and compare them with some haphazardly checked bullets and see for yourself if it matters. (But don't bet against the perfectly checked ones.)

Did you experiment like this yourself? I won't argue against the results of a well conducted experiment, but it seems to me that the gas check that is not perfectly seated will move before the bullet begins to move and would be flattened against the base of the bullet "long before" (imagine that, if you will!) the bullet ever even clears the case mouth. I do not follow your meaning when you say "If the check is seated crooked it'll be pounded crooked." What am I missing?

A misaligned check (especially if using an in and out sizer like the LAM or Lyman that sizes/swages the check first) can misalign the entire projectile and can be visibly seen with round ogives and to a lesser extent with square driving bands.

Runout gauges can be used for cast bulleted loads just like we use them for jacketed and probably aren't used enough before the fire lights. Other than the seam blips, you want them holding under .005.

Nose first sizing, using a perimeter cupped punch, indexes the check on the side (diameter) of the shank and doesn't rely on a perfectly square shank and isn't effected by a raised sprues either. More importantly it allows the length of the bullet to center the check, not the other way around. It also eliminates "crooked", provided the cupped punch is square.

Yes, shooting them side by side will show you thats whats misaligned when the fire lights won't be corrected when it does.

Yes indeed I've experimented, inadvertently at first. I remember years ago creating a batch of .30 rifle bullets whose checks were obviously canted on the bullet bases. I shot them anyway and accuracy was so-so. I then re-created the same bullets (same alloy, same sizing/lube, etc.) but took pains to perfectly seat the checks (with a homemade GC seater in a tiny arbor press, after first tapering out the GC walls with another homemade punch in the same arbor press so they fit flat but loose on the bullet base before being seated) and re-fired with the same brass (brass prepped exactly as with the first batch). Accuracy was significantly better, with nice round groups instead of asymmetrical groups with "unaccountable" fliers. (Winchester Model 54 .30-30 with 10x Unertl, if it matters, custom Saeco 190 flat point, 28gr. 3031 according to my notes.)

Made a believer out of me, and firmed the notion that the bullet's base truly is the steering end. Such pains as described above are employed with all the GC'ed rifle bullets I shoot now - when the nth-degree of accuracy is desired - but will admit to doing it the sloppy way in the lubrisizer when all I'm doing is concocting plinking ammo. HawkI's method is an elegant one and may need to be tried too, but my trouble is I find myself shooting an inordinate amount of plain based rifle bullets over GC'ed bullets anymore so that may or may not happen.

Thanks for typing all that out. I never doubted the importance of a good square bullet base, but always wondered if pressure at the instant of firing would take care of any incomplete gas check seating. My intuition says that it would, but intuition just doesn't always paint the right picture.

Those inadvertent experiments can be eye openers if you're paying attention!

Gas checks are seated while being pressed through the Lyman 450 press heal first, which means gas check first. This properly aligns the check first and then gradually crimps it in place further down the H&I sizer die when it reaches finished resized diameter. I like .001", or so over slugged barrel groove diameter. I also know when to give the lube handle a crank to squeeze lube into the grooves. They always come out looking really nice, though I usually have to wipe some lube off the base.

I think I have 3, maybe 4 GC revolver moulds & if it calls for a GC I use one, just a habit I've had for over 50 years. For the most part I just shoot plain base bullets & take lots of game with them, especially now that I've been powder coating for the last 10 years or so. I've ran some pretty dececent velocities & some very decent groups, (considering) 80 year old eyes....all most.
But with my 327 8 shot gun, my 357 Maximum & one of my 41 magnums that I tend to hot rod a bit in my 10'' FA those moulds call for GC's & I happily apply them using a Lee sizer die kit, easy peezy! It can be a little bit hard to seat GC's with the Star sizer or the RCBS sizer, I do it the easy way with the Lee sizer, never fails. And I use one top punch for the Star for all bullets & one top punch for the RCBS, both are flat, so they self align the bullets.

Dick

If the bullet is designed for a gas check, use one. If not .. sort obvious, but don't. The base of the bullet is where the magic happens .. good and bad. If you're going to use bevel based bullets, I'd recommend either PC or a Star sizer. BB is tougher with RCBS/Lyman style sizers. Star is .. or was .. pretty expensive.

I would probably pick a non gas check bullet for revolvers and semi-autos, gas checked for rifles.

That was just what I was going to say.
+1

As others have already said, if the bullet base is designed for a check then use one. When I started casting Lee 440gn bullets for my 500 Magnum, gas checks weren't available so I tested them without checks but with a heavier powder coat on the base. Most had no issues but some had severe gas cutting and poor accuracy. In the pic you can see the base was fine and the gas cutting started at the lower drive band and continued all the way through the top band. Nearly all the gas cutting occurred over 1500FPS. Once I started using checks the gas cutting stopped and accuracy was noticeably improved.

Thats not gas cutting.

Thats the area of the bullet where pressure and friction is the greatest. If the gas were "cutting", it would do the same on the bare check shank. It does not.

Its also looks possibly undersized, at least I don't see any rifling imparted? Another sign of of friction= slippage from not having full diameter support and seal.

A gas check does several things. It hardens the base where pressure and friction is greatest and doesn't melt.
It also scrapes fouling keeping bore condition consistent at high temps, where lead loses some strength.

Thats a good recovery though!

If you are PC'ing a gas checked bullet, do you PC first, then apply the GC or apply the GC first, then PC?

I usually put the gas check on first since powder coating will often make the gas check shank too large so it is difficult to seat the check squarely.

Put the gas check on after PC and before you size the bullet.

It does not matter when you put the gas check on. Some shanks will let you put it on after you pc while others will not. The only way is to try both ways and see what works for you. If you are using aluminum then usually always put it on after you pc. They have a tendency to fall off while putting the powder on.

The person I commented on with "gas cutting" issues powder coated his bullets, yet clearly had leading that he related to "gas cutting" at what he stated was 1,500 fps..

I'm still using traditional lubes at 2,900 fps (with a gas check), but most are around the 2,500 mark in the cartridges I use.

Please explain to me how powder coating can allow me to push to higher velocities than I am currently getting.....if that can't be explained, then why is a bullet with a gas check shank more accurate with a gas check installed?

Thanks.

We have to make an assumption, Hawk, that the PC /leading situation didn't involve an improper PC'ing, ie: a wispy thin coating that would wear through in a thrice.

At those velocities and traditional lubes you've carried through the then groundbreaking experiments by a handful of determined guys 40+ years ago. Kudos to you! Sometimes the easy way out (PC'ing in this instance) isn't a panacea rather merely an alternative. The Johnny-come-lately's to the hobby maybe never knew that PC'ing came about as an alternative means of achieving high "hunting" velocities with alloys soft enough to expand yet not horribly lead the barrel, not necessarily a means for ignoring some of the basic precepts of cast bullet shooting.

Not sure I understand the question in paragraph 3. I will say though that perhaps a GC bullet sans gas check presents a disruption to the air flow as it transitions from the side of the bullet to the base - air flow uninterrupted by the naked stepped base would flow cleanly and swirl uniformly against the flat bottom? That's my theory anyway. Me, I'll continue using gc's where they're supposed to be, even when dabbling with slow velocities because I've proved to my satisfaction that a gc'ed bullet at low velocity with its gc in place is generally more accurate than without. Sometimes not a helluva lot more accurate, sometimes a great amount more accurate, but pretty much always more accurate to one degree or another.

Powder coating allows the use of softer alloys. The step in the bullet base focuses pressure and heat against the first full diameter band of lead on a gas checked bullet design. Velocity is not the Holy Grail in cast bullets.

I worry more about the sprue cut on the base of the bullet kicking the gas check crooked. Even sanded a few to remove the cut but never “proved” it helped.

A cupped punch or liftout plug will work "around" a raised sprue.

You can create a very hard alloy with WW, lino and magnum shot using very high heat. Then cast your bullets using ingots in your drop pot with frequent fluxing and water drop the bullets. These bullets could then be heat treated. Instead, you can use Eastwood chrome plating, black, to double coat and double bake them, nose down in a hardware cloth upside down box, then size the PCed bullets to the exact groove diameter. They will do 2,400 tp 2,500 without leading in a rifle. I use the plain base RCBS 200 grain 358 with no gas check and no leading in my 35 Whelen and 358 MGP AR-15s, two and get sub 1/2" groups at 100.

You are not doing something correctly, if you get lower velocity leading.