Cast Bullets in Glocks...?

[BrassFerret]

Hey Guys
This topic has more than likely been beaten to death over a hundred times, so I apologize for asking it once again! Also, sorry I joined this forum a few years ago and have not posted. So, here is a brief bio about me...

I live in South Africa. I enjoy hunting, reloading, casting bullets (of course!!), mountain biking and being outdoors. I hope that is enough, feel free to ask if you want to know more. There are some things i cannot answer...

I own three Glocks;
Glock 19 Gen 3 9mmP
Glock 17 Gen 5 9mmP
Glock 41 MOS Gen 4 .45ACP

I love casting...can I safely use cast bullets in these handguns? I use White Label bullet lube and haven't started with Powder Coating my bullets, so this only applies to traditionally lubed cast bullets.

What is or was all the hype about regarding cast bullets in Glock handguns?

Thank you all!!!

 

[Ian]

More than likely? Understatement of the week . Welcome to the forum!

I assume you're referring to the infamous "polygonal rifling" of the Glocks which is known to collect lead fouling to the point that pressures become excessive. The fix for that is well-established and involves making sure your cast bullets are large enough to seal all the gas in the bore, otherwise the corners of the lands leak and lead washes out around the bullet and leaves heavy deposits in the bore that accumulate rapidly. I don't believe powder-coating will fix this unless the undersized-bullet issue is also fixed, the coating will wash out almost as easily as lead will in my experience so the bullets still must fit the bore tightly when engraved or you will have problems.

The two 9mm pistols will present the most challenge because the brass is very hard and the reloading dies commonly available tend to make the brass too small for cast bullets. The tight, hard brass can crush your cast bullets when they are seated, making them undersized for the bore. Many handloaders find that using a larger than normal expanding die prevents this. You will have to seat bullets and pull them out again to measure and compare to a bore slug to ensure that the bullets are not getting sized smaller by the brass.

The .45 ACP should be fine with .451" or .452" bullets, depending on your pistol's throat entrance diameter and groove diameter. Most standard reloading dies for the .45 ACP work fine with cast bullets with no modifications. Hope that helps.

 

[Pistolero]

I don't own a Glock, but the topic has been wrassled with a lot. Many have had no issues with lead bullets in
Glocks. I think Glock was looking to point the blame away from their "perfect gun" and grasping at any excuse
when the guns failed.
A friend blew up a .40 S&W Glock with a lead bullet handload. Glock, of course, blamed the handload. He got another
one, put in a Barsto barrel and loaded for it without problems for years. IMO, the very sloppy chambers and generous
feed ramp unsupported area of brass contributed to blowups in early Glock .40s - WITH FACTORY AMMO - and with
handloads, too.

Now - let the Glock experts correct my comments, and probably add tons of hands-on wisdom.

 

[Ian]

He's got Gen 3 or better and no .40, he's good to go there.

 

[fiver]

it has been speculated to me that part of the glock ka-booms were because of layering in the barrel making process which finally delaminated in front of the chamber.
I dunno I don't own nor plan on owning a glock so I didn't question or investigate any further.

anyway.
over the years the guys that have had success with cast in them have pretty much done so with larger and slightly harder bullets similar to what you'd use in a marlin lever gun.
you'd be wise to look for leading in the places Ian suggests may happen and use that as a guide.

 

[BrassFerret]

More than likely? Understatement of the week . Welcome to the forum!

I assume you're referring to the infamous "polygonal rifling" of the Glocks which is known to collect lead fouling to the point that pressures become excessive. The fix for that is well-established and involves making sure your cast bullets are large enough to seal all the gas in the bore, otherwise the corners of the lands leak and lead washes out around the bullet and leaves heavy deposits in the bore that accumulate rapidly. I don't believe powder-coating will fix this unless the undersized-bullet issue is also fixed, the coating will wash out almost as easily as lead will in my experience so the bullets still must fit the bore tightly when engraved or you will have problems.

The two 9mm pistols will present the most challenge because the brass is very hard and the reloading dies commonly available tend to make the brass too small for cast bullets. The tight, hard brass can crush your cast bullets when they are seated, making them undersized for the bore. Many handloaders find that using a larger than normal expanding die prevents this. You will have to seat bullets and pull them out again to measure and compare to a bore slug to ensure that the bullets are not getting sized smaller by the brass.

The .45 ACP should be fine with .451" or .452" bullets, depending on your pistol's throat entrance diameter and groove diameter. Most standard reloading dies for the .45 ACP work fine with cast bullets with no modifications. Hope that helps.

Thank you Ian

That brings out another question... I tried slugging my Glock 19 barrel. I am having difficulties measuring across the 'flats' and 'corners'. A bit of a problem... I was just wondering if I just sized them at .356 or .357'?

I load on a Dillon RL550, so I can try turn or polish a .357 powder funnel down to an appropriate diameter. I would guess I should 'shoot' for about .001' under bullet diameter?

Thank you for your reply!

 

[fiver]

I'd be more inclined to run them at 358.
the only 9's that seem to need 356-357 to function well are sig's and the like.
you might even be better off with 359.

 

[Pistolero]

I suggest .357 or .358 for most 9mms, too. Way more problems have been related to too
small than too large, esp in 9mm. And the only issue with "too large" is, will it chamber? Be sure to make up
a dummy round with .358 and see how it will chamber before loading up 300 .....
Some 9mm have tight chambers.

Bill

 

[CZ93X62]

Glock 9mm, 10mm, and 40 S&W are of hexagonal form--45 ACP and 45 GAP are octagonal form. They are a little tricky to 'slug' properly, with their "lobes" and "flats". Spend your effort on the wide lobes--those are the wide spots spoken of above. Also try to get that throat specs if possible, using a slightly oversized pure lead slug or roundball.

E.g., some years ago I slugged my Glock 21(45 ACP) and came up with .453" throat and .449" x .452"+ flats and lobes. Not quite .453" on the lobes, a few tenths short. I put together a test sequence of about 200 each of .452"-sized bullets and .454"-sized bullets, 4 designs/50 each. 400 rounds later, zero leading with either diameter. 45 ACP is very lead-friendly anyway, alloy was fairly hard (92/6/2) and lube was 50/50 Alox/BW. Warm temps in desert that day, topped out about 92*. .452" vs. .454", both shot well and did not produce lead deposits.

I have just started out with 40 S&W and 10mm and cast bullets. 2 of each caliber and OEM barrels--all have throats a few tenths over .401", lobes are all a few tenths under .401". I have yet to fire any rounds through these pistols, but I will give .401" sizing that has worked well in a lot of other 40 S&W and 10mm pistols over the years. If any reports of mushroom clouds rising up in southern California's desert show up, you'll know that cast bullets were a non-starter in Glock 10mms. And to be clear--I was NOT shooting cast bullets near Ridgecrest in Glock 40 S&Ws on July 4th and 5th.

There may be another Glock in 9mm here before much longer. The G-19 that lived here previously went to WA with its user to grad school at U-Dub.

FWIW--one of the most exaggerated polygonal bore forms ever developed--the Whitworth rifle--just dotes upon pure lead bullets.

 

[KeithB]

Not a Glock but I use .358" lead in my HiPower, seems to work fine.

 

[RBHarter]

I haven't shot much cast in the G42 but what I have is .358 in 380 auto . (9×17 , 9mm Kurtz .) Little to no leading , mostly what's there looks like it's sticking to copper streaking . I'd guess maybe 2-300 rounds down range I expect the peak/flat OD is .356 . I got lucky with my expander it runs mouths out to .356 , I have a 38/357 pin in it .

 

[Tomme boy]

I have a g26 and a g19. I load both with 0.358". I don't get any leading with plain cast or powder coat. The 19 has a shorter throat so I load them to what the 26 chambers freely. But the chamber itself on the 19 is a little tighter. It is a gen4 while the 26 is a gen 3. I also don't get any belly stretching from a unsupported chamber. Be careful of your crimp and don't use a Lee factory crimp die.