BHN and Gas Checks

[metricmonkeywrench]

As I was seating some 35 cal gas checks on some 358156 for the first time and pondering the meaning of life the universe and everything, I got to wondering what is the high and low end of the BHN range for gas checks.

Straight lead is probably not worth the effort and on the high end there is likely a hardness where a gas check doesnt matter.

For this batch I cast the bullets out of my 14 BHN that I have been using for rifle bullets, but I also have a bunch of 10.4 range scrap that I have been using for .38 wadcutter.

(BTW the answer is 42 of course [smilie=p:)

[BrutalAB]

But what is the question?

[metricmonkeywrench]

the answer to life, the universe and everything of course

Nothin on the bhn though?

[kungfustyle]

the answer is 42, just kidding Hitchhiker's guide to the galaxy. But 14 should be a great candidate for gas checks. It does matter on the bn, people will chime in with all answers. For me, anything over 1400 fps, gc. PC from 1000 to 1400 and your good to go. Anything over that and you still should have a gc. If you want just lead, look at paper patching. That will work with the 10 or 14 bn. You may be able to eek out a bit more out of 20/22 bn but its not worth the expense of extra tin/antimony. If you want to go 2300fps buy speer for $.17 each on sale IMHO

[cwlongshot]

As a rule if a bullet calls for a GC it gets one.

My PC has proven again and again it negates the “need” for a GC up to nearly 2K velocity.

I Just was GC’ng some experimental hardness BHN7 220g HP MiHec bullets. I’ll Powder cost then later today. The GC for me (after PC) is to provide a important perfect bullet base. Not so much to protect against heat and pressure.

CW

[JonB_in_Glencoe]

Yesterday, I also was pondering the meaning of life, the universe and everything. I was loading some 410610 (a 41 cal SWC very similar to the 35 caliber 358156). The previous day, I had worked up a load to Max for my 3" 657.

The GC'd 410610 boolits I had cast a couple years ago, and sized/lubed them last year. My notes said they measured 16 BHN at a couple weeks old. I checked a few before loading the test loads on Monday, they measured 18 BHN, I was kind of surprised. I had to look up the alloy, it was automotive Battery Term Lead with 10% lino added. That added hardness is part of the reason why I thought I'd load up this batch of boolits with a worked up "Max" load of 2400.

The next batch of boolits that I had lying around, is some MP413640 that another member PIF'd me on Christmas 2017. They were suppose to be cast from COWW, I measured them in 2017 and they were 12.0 BHN. I measured them yesterday and they are 12.5 BHN...No surprise at all. I'll load these these up with Ken waters Pet load of Alcan AL-7.

So that also happens to be my answer of what is the high and low end of the Boolit BHN range for gas checks in 41 cal pistol.

PS, when I tested those 2400 loads on Tuesday morning, it was 15º F and breezy...but the sun was out. The top load was 17.7 gr. and it really slapped my hand, but good. I hope the felt recoil will be lessened with summer arrives :wink::Fire:

[swheeler]

As a rule if a bullet calls for a GC it gets one.

My PC has proven again and again it negates the “need” for a GC up to nearly 2K velocity.

I Just was GC’ng some experimental hardness BHN7 220g HP MiHec bullets. I’ll Powder cost then later today. The GC for me (after PC) is to provide a important perfect bullet base. Not so much to protect against heat and pressure.

CW

You are mistaken. That statement needs to include bullet diameter/caliber and even weight can change things. In my experience PC is a great lube but very little more. Add a little HBN to the PC even better lube

[cwlongshot]

You are mistaken. That statement needs to include bullet diameter/caliber and even weight can change things. In my experience PC is a great lube but very little more. Add a little HBN to the PC even better lube

Haha. How can I be mistaken? Where ya shooting with me to see what my bullets did in my gun? Did ya see something I missed while shooting? ;)

I didn’t say everyone’s would be same (But I’ll bet they will) I said “my PC”. I would go so far as to say Good quality PC, if PROPERLY applied, will do same as I claim in the majority of firearms to 2000 FPS. I am in no way alone in this claim.

As to doing the kid of a GC. PC will NOT REPLACE A GC. PC will not always and across the board eliminate the need of a GC for some bullets. What it WILL DO, is raise the velocity threshold, where a GC might have been required. In some calibers that will never again that threshold velocity reached, yes a GC requirement could be eliminated. But NOT all calibers.

I have shot it from 22 CF thru big 45’s and every diameter hand gun in between sans 25 hand guns. I don’t have a 50 hand gun anymore. I have also shot my PC thru a bunch of rifles too, many 35 & 45 cal rifles from the lil 357 Mag thru my 358 Norma Magnum 45 auto thru 45/90.ALL with ZERO LEADING & ZERO FOULING associated to the PC bullets. Personally 2000 is fastest I have pushed them. My 450 Bushmaster has been loving a few designs powder coated at 1850 ish.

It’s not a end all be all But it’s working as well as I could hope and I love it!

Good luck,

CW

[swheeler]

"Did ya see something I missed while shooting?"
Yep, it was the 405 gr plain based PC bullet at 2000 fps from your 45-90, couldn't see round holes in the target at 100!:coffeecom

[Dragonheart]

You are mistaken. That statement needs to include bullet diameter/caliber and even weight can change things. In my experience PC is a great lube but very little more. Add a little HBN to the PC even better lube

Sorry but he is right! Assuming a properly coated and sized bullet.

A gas check will improve accuracy if it is installed properly as it will provide a perfectly flat and perpendicular base. Since a bullet designed for a gas check has a very imperfect base without a check, powder coating will alloy one to shoot the bullet at full power, but accuracy is another issue. A polymer jacket will withstand the torque spin up of 50K pounds of chamber pressure, so a polymer jacket is far more than just a lube.

[swheeler]

Sorry but he is right! Assuming a properly coated and sized bullet.

A gas check will improve accuracy if it is installed properly as it will provide a perfectly flat and perpendicular base. Since a bullet designed for a gas check has a very imperfect base without a check, powder coating will alloy one to shoot the bullet at full power, but accuracy is another issue. A polymer jacket will withstand the torque spin up of 50K pounds of chamber pressure, so a polymer jacket is far more than just a lube.

What good is it if you can't hit anything? :bigsmyl2: Pc has worked better for me than what I tried first, HiTech but neither is better than CRed or any GOOD lube with the correct alloy on a conventional GreaseGroove bullet. I guess maybe that is the problem I don't own any smooth sided bullet molds made just for PC that could take the pressure and maintain accuracy. I've shot plenty PC bullets by now, into the 10's of thousands mostly pistol but plenty rifle too, in a half dozen calibers it's great but not magic. It's been quite a few years since starting with this stuff, about the same time you did, I just try to keep it real, the BIG stories are for fishing, I could probably beat you and CW both in that venue!

[cwlongshot]

Probably so my friend... probably so.

Enjoy

CW

[metricmonkeywrench]

Sigh... who let the PC crowd in...

[John Boy]

My rule of thumb: GC bullet base - under 1600 FPS and alloy less than Lyman #2 = no GC.
Over 1600 FPS -= GC and alloy greater than Lyman #2

[Cosmic_Charlie]

the answer is 42, just kidding Hitchhiker's guide to the galaxy. But 14 should be a great candidate for gas checks. It does matter on the bn, people will chime in with all answers. For me, anything over 1400 fps, gc. PC from 1000 to 1400 and your good to go. Anything over that and you still should have a gc. If you want just lead, look at paper patching. That will work with the 10 or 14 bn. You may be able to eek out a bit more out of 20/22 bn but its not worth the expense of extra tin/antimony. If you want to go 2300fps buy speer for $.17 each on sale IMHO

I think the chamber pressure is more relevant than the velocity. I was shooting some 240 grain jhp over 14 gr. of 2400 yesterday out of my .44 special and liking the accuracy. Thought my 250 Keith boolits might work well if I cast them out of Lyman #2 with that charge.