Home Forums Hunting & Shooting Handguns "Heavy" 10mm loads in Glocks

After my problems with Buffalo Bore 220gr HCL loads (would not cycle or feed), and Double Tap 230gr HCL (fed poorly, case ruptured on 3rd shot) in my G20, I emailed both companies - explaining my problems came with a 6" Lone Wolf barrel, and that since replacing that barrel with a Glock 6" barrel the ammo will feed (manually) fine, but I am a bit hesitant to fire it. I got a very quick reply from Tim Sundles of Buffalo Bore. He said that they "keep hearing" of problems with their ammo and Lone Wolf barrels, he recommends using Glock barrels and factory recoil springs, as that is what they used for development work on the ammo, and it should work fine.

I have already replaced the stock recoil spring with a 22# spring and the plastic guide rod with a SS one, and will be keeping these, but maybe I'll give the ammo another try? He also said "do NOT worry about the unsupported
case web area because 10MM brass is very strong in the web area unlike 40
S&W brass." Hmm. I have a picture of a Double Tap "blown out" in that area, but what do I know? I was just pleased to get such a quick response.

Like I've said before on here, I have about 1200 multiple fired cases I handloaded before knowing about the unsupported case problem. They were mixed mfr. I load for accuracy but have found that is usually near the top for my Glock 20 so most of my loads were at the top or nearly so. I probably loaded most cases 2-3 times. Maybe more. I never found one that had a bulge in all the operations of case prep, or a split, and watched on the last priming very carefully to find one. I never found one.

That being said, neither do I believe that my handloads were approaching the pressure of BB or DT loads. If it were me, and I wanted to load some stiff hard cast loads, I would purchase the bullets from DT, Cast Performance, or Beartooth (cheaper and shot good in my gun) and load my own within published recommendations.

I'd also use the barrel that supports the case the best and if it doesn't chamber correctly send it back. I have a Storm Lake barrel and have used it for a couple years and never had any issue with it not chambering or shooting my handloads if properly crimped with a Lee factory crimp die.

I've seen other posters talk about their 10mm loads for auto pistols on here which are 1 grain above "book" max for heavy bullets. Personally, I don't believe that is a good idea and may well be where problems or kabooms come from. Each to their own.

If you (rhetorical "you") need more juice in an auto pistol than 10mm provides, I believe the best alternative is a Desert Eagle, not trying to make the 10 into something it cannot safely become.

Thit is, indeed quick and good response and service!

About 10mm brass having thicker web areas and just forward, I have not been able to detect that and especially not in some of the 10mm loads that blew right through the cases when I was testing some ammo in my Delta Elite. I have seen plenty of 10mm cases with little 'smiley face' creases in the brass where the case was unsuported, too.

Go forward with all due caution and discretion. When I am testing a new formula in a handgun I wear thick leather gloves and the best eye protection I have on hand.

With my stock Glock 20 10mm barrel there is feed ramp intrusion to 0.288".
10mm brass has a 0.180" thick web.
That leaves .108" of thin unsupported case wall over the feed ramp.

My Barsto aftermarket Glock 20 10mm barrel has case support to 0.230" -> 0.050" of thin unsupported case wall.

I can measure the effect of the difference with overloading work ups.

Hodgdon published max load 10mm:
9.5 gr. LONGSHOT max Hodgdon, 180 gr. SIE JHC, WLP, 1.260", 5", 1287 fps 34.6 kpsi

Stock Glock 20 10mm work up
a) 9.5 gr. G20 stock, WLP 1.26", 180 gr. FMJ FP .58", ok, 0%
b) 9.75 gr. G20 stock, WLP 1.26", 180 gr. FMJ FP .58", bulge, 3% extra powder

Glock 20 Barsto barrel work up
a) 13.2 gr. G20 Barsto, WLP 1.26", 180 gr. FMJ FP .58", bulge 0.230" , 39% extra powder

I should add that:
1) Longshot may look good on paper, but cannot produce much power compared to 800X
2) The real limit in well supported 25acp, 32acp, 380, 9mm, 40sw, 10mm, 45acp, etc. is recoil and not pressure as is commonly misconceived. The practical and common [slide mass * recoil spring] products are going to be too small to avoid slide slam. Slide slam is bad for the hand, bad for the gun, and makes the ejected brass hard to find.
3) Measuring a case in a chamber and scribing feed ramp outline will produce a measurement a few thousands smaller than measuring the bulges. This explains the inconsistencies over the last decade in my posts on forums and quotes of me on the gunzone.

Looked over the small collection of fired brass I have, and didn't really see any creases or smiley faces - just some that appeared to be scratched, maybe from extraction. This included the 7 or 8 Double Tap cases I fired before I got the rupture, in the Lone Wolf barrel. I sent a picture of my ruptured case to Tim Sundles, and he said that IF the round was not overcharged and IF the brass was in good shape, case support should not have caused that. He said if the brass was marked Double Tap it was probably Armscor, and theirs was normally good brass.

His recommendation from the Buffalo Bore point of view was to only fire their rounds (in a Glock) through Glock barrels. I will be taking that advise, and I will try to shoot the BB and DT rounds I have left, CAUTIOUSLY. Although I am a fan of heavy for caliber Hard Cast bullets at low velocities, I intend to shoot jacketed hollow points at the higher 10mm velocities, higher being relative to .45ACP or maybe sub sonic .44 mag. - most likely 1200 fps or under.

Also, thanks to you fellows (Clark, Mark, RickyD) for helping by sharing your own knowledge and experience. I am listening and learning.

Here is hot loaded 10mm with the lonewolf barrels. They don't support any better than the factory glock barrels. I have yet to see a barrel that fully supports the case in a glock. Some are better than others but none are full. I promise youif you were to reload this brass again, you would be a kaboom just waiting to happen. I love glocks, own a couple but I know the limits of em.

I'm loading 200 grain xtp & double tap hc with 9.3gn of Longshot and using a cci mag primer in a glock 20 with a kkm barrel at 5.5" long. I have some brass on its 5th loadings and no sign of a bulge. My chronograph says 1275fps. I have about 700 rounds fired and never got a bulge. 22# spring and stainless guide rod.

That is good information, High Country, thanks. Is a magnum primer necessary with Longshot? Haven't used it yet, powder selection locally is very poor right now, to say the least.

What Ricky D said. E

I don't think a magnum primer is necessary, but I was able to find 5k of them.....so that is what I am rolling for now.

I got a call today from Double Tap ammo, about my recent "kaboom" problem. After telling me that he used a LW barrel in a G20 with no problems, except that often the ammo would not fully seat in a "drop test" and would need to be "pushed" the last little bit, I was told that the wide face on the 230gr Hard Cast bullets sometimes cased problems, and that perhaps I should consider a 200gr bullet. DT ammo loaded with a 200gr Nosler JHP was highly recommended (I have a box of these bullets to load already). Then I was told that DT did have a problem with some brass from a new supplier they were trying, so they offered to send me a box each of their ammo loaded with the 200gr Nosler and their own 200gr Hard Cast in exchange for me sending back the two boxes of 230gr Hard Cast I bought out of which I had the case rupture, so they could check the brass to see if it came from that bad batch.

After getting good and quick response from Buffalo Bore, also, I am maybe more impressed with the customer service from these ammo providers than I am the 10mm cartridge itself!

That IS good customer service!

Glad it is all working out for you.

Not every ammunition maker is a member of SAAMI, keep that in mind. I would feel quite confident with ANY SAAMI spec load in a Glock 20. Beyond that, I really don�t see that you gain much with +P; maybe 100fps, but a good decrease in safety margin. Are you willing to give up a good deal of safety margin for 100fps? Do you think anything you shoot with 100fps less velocity will be significantly different from something that has the extra 100fps?

When you go beyond SAAMI, you�re trading safety for performance. It�s up to YOU to weigh the risk vs. benefit.

Personally, I can�t imagine there�s anything that is hit squarely with a full power 10mm load and won�t go down, but will with 100fps more. Color me dubious.

I say, if you�re carrying a Glock 10mm you�re the last guy in the world who needs +P�you have like 14 more chances at success available to you instantly.

This bears repeating.

Kevin, you are correct, of course. I don't intend to "push" the 10mm past levels proven to be safe. If I need more than that, I'll carry my .44 Mag, or one of my Contenders.

On the 14 more chances, though, often a game animal that does not go down does not give you 14 more chances to "make it right", - and my use of the 10mm will be for hunting.

Too late.

IF your choice of a 10mm is for hunting, I think you would be far better off with a 1911 style pistol that has a fully ramped barrel. You would gain an immensely better trigger, better ergo's, a slimmer profile and with said fully ramped and thusly full coverage of the case barrel the Doubletap and Buffalo BOre stuff as well as handloads that replicated the original Dornaous and Dixon / Norma loads could easily and safely be digested.

The Doubletap, Buffbore etc. strike me as merely being what the 10mm auto round was intended and designed to be.

You have posted this statement several times and it is IMHO a statement that borders on unsafe. THE 10MM WAS BACKED DOWN BY SAAMI BECAUSE THE TOP LOADINGS WERE EXTREMELY ABUSIVE TO THE GUNS AND OVER TIME UNSAFE. When one comes unhinged in your hand it will not be a pleasant experience.

Re-read Kevin's post above there is much logic in it

Mark,

I assume you mean building up a custom 1911 with a ramped barrel? The standard 1911 barrel is non-ramped and really doesn�t offer much more case support than the Glock (a little, but not much).

But you could do a ramped barrel in the 1911 and that would give you more case support. Or one could go with the Witness 10mm which is a very good, often overlooked, completely underrated, high capacity 10mm pistol with a single action carry option. They even make a �hunter� model with longer barrel and single action.