My Full Power 10mm Load workup

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Here's my full power 10mm load workup
I tested two barrels in a Glock full sized G20. An Alpha Wolf fluted, fully supported, threaded 5.3" barrel. And I tested in the OEM glock 4.6" barrel.

A couple initial notes, the Alpha Wolf chamber is considerably tighter. It wasn't until I got to the very top end of the load that brass fired in the Alpha Wolf barrel would not easily slip right into a chamber checker. So not only is the alpha wolf barrel longer, the chamber is more snug. Brass fired in the factory glock barrel stopped fitting in the chamber checker even at lower pressure loads.
Also, I used a 22lb captive recoil spring.

First, I have chonographed a bunch of 10mm factory ammo. I have found that only Buffalo Bore Full power factory ammo hit almost exactly what the box says it will. Underwood and double tap were 50fps-75fps lower than what they are supposed to achieve. Lower power loads like Federal and Speer did achieve the box flap stated velocities.

I use a few known loads in my 44 mag to ensure accuracy of the chroney that I have verified with 3 different chronograph.

CAUTION: The following post includes loading data beyond or not covered by currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.

A note on the powder. I used longshot because it meters better than 800x (which is terrible), it has a lower muzzle flash than blue dot (which is terrible), and accurate #9 was out of stock everywhere or else I might have tried it too. Supposey VVN105 works well too.

Here's the hardware info
Starline Brass
WLP Primers
Nosler 200 gr JHP bullet
Hodgdon Longshot Powder
COAL 1.255"
Crimp .4210

I did some initial testing at lower charges but I'll skip to the higher charges.

8.2 Gr long shot (20 rnds)
Alpha Wolf 5.3"
Avg 1201 fps
Low 1181
High 1212

8.2 gr longshot (10 rnds)
Glock OEM 4.6"
Avg 1137 fps
Low 1111 fps
High 1151 fps

Small glock bulge on the OEM fired brass. Nothing note worthy with Alpha Wolf brass

8.4 gr Long shot
Alpha Wolf 5.3" 15 rounds
Avg 1213 fps
High 1229fps
Low 1196 fps

8.4 gr longshot
Glock OEM 4.6" barrel (10 rounds)
Avg 1142
High 1159 fps
Low 1131

More pronounced glock bulge from OEM barrel. Nothing remarkable with Alpha Wolf barrel.

8.6 Gr Long Shot (15 rounds)
5.3" Alpha Wolf
Avg 1228
High 1247
Low 1219

8.6 gr Longshot
4.6 " OEM barrel (10 rounds)
Avg 1153 fps
High 1171
Low 1136

Notes: Nothing remarkable with Alpha Wolf barrel. Glock OEM brass bulge easily visable.

8.8 Gr long shot
5.3" Alpha Wolf barrel 15 shots
Avg 1239 fps
High 1257 fps
Low 1226 fps

8.8 gr longshot
Glock OEM barrel 4.6" (12 shots)
Average 1170
High 1188
Low 1151

Notes: Same as 8.6 gr load....Nothing else remarkable

9.0 gr Longshot
5.3" Alpha Wolf barrel (15 shots)
Average 1254 fps
High 1267
Low 1244

9.0 gr Long shot (15 shots)
Glock OEM barrel 4.6"
Avg 1189 fps
High 1207
Low 1177

Notes: Alpha Wolf brass no longer slides easily into chamber checker. Glock brass with very visable bulge. Primers beginning to flatten on Alpha Wolf brass.

I
My goal was to see if I could safely make a 10mm load that would get 1250 fps with a 200 gr bullet and around 1200 fps with the OEM glock barrel.

Velocity wise this is similar to the old Norma load and some of the current buffalo bore production.

If the 9.0 gr load is fired in a Glock OEM barrel, brass life is going to be short.

The chroney went on the fritz due to mist and rain but I further pressure tested up to 9.3gr Longshot in .1 gr increments and I noticed glock smiles on a couple pieces of brass fired in the OEM barrel and the alpha wolf barrel brass at 9.3 gr began sticking a little. Also, it would no longer fit at all in the chamber checker. I did this just to see how close I was to the upper limit.

So there you go, I would need to switch to 800x powder or a longer barrel to safely do any better velocity wise. But 1250 in my alpha wolf barrel and approximately 1200 in my OEM barrel is a stout load in my opinion.

Now we can cue the safety police comments from the manual limit zealots :rolleyes:






****Update**** once I cleaned some of the brass really well and further examined it, I noticed the very beginnings of glock smiles appearing at 9.1 gr.
I would not reload glock smiled brass. Bulges yes but smiles no.
So in short, I personally will fire the 9 gr load in an OEM glock barrel but wouldn't reload it. And it will probably need to be newish brass.

I have no concerns in the fully supported alpha wolf barrel reloading this, though the primer pockets may start to loosen up sooner than they would have otherwise.
 
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Great info. Thanks for posting your results. I dont load 10mm, but I do load .40 SW. I just checked Hodgdon Reloading data center, because I bought Longhshot for .40 SW. Comparing your Glock OEM barrel results to Hodgdon's, using Longshot you can get the same velocity as 10mm 200gr. with 40 SW 180 gr. I like this point because, giving up 10% weight, you can do as well with the 40. The relevant question, to me, is do I need a 10mm, to materially outperform the 40? For me that answer is no. So I go back to looking at Glock 30 in 45, and wonder if I can gain on 40 anymore so in a 45 chambering.
For carry, I do prefer the less than fullsize Glock, especially if working in a vehicle. The 30 and 31 are already at Calif mag capacity limit of 10.
 
I also reload 40.
My standard practice load is 180gr jhp at 1050 from a full sized M&P 40. It's a snappy load from my full sized M&P and very snappy in my m&p shield.

A better comparison though, pound for pound is a 180 gr 10mm and 180 .40 s&w. The 10mm will do 1350-1400 fps with a 180 gr bullet.

However, your point is valid, in that a full house 10mm load is over kill for many applications.

I bought the 10mm for hogs and because you can use it on deer too. Buffalo bore makes a 230 gr hard cast load that 1200 fps that would be a show stopper for pretty much anything.

Full power 40 s&w isn't too hard to find while full power 10 mm , with the exception of Buffalo bore and maybe a couple others, has to be made .
 
I have noticed later Glocks are better supported than early Glocks. 9mm, I don't differentiate the empties, although I shoot through a Glock barrel and a Lone Wolf. In 40 SW, I think mine is a Gen3 G23, I police my nickle cases, and size and load again. If it will size, and chamber, and they always have, they keep going. My acquisition of Longshot is recent and I haven't loaded with it yet, but I will certainly be scrutizing my cases. In fact my Glock loading has always been target velocity.
I understand the "bulge". What is Glock "smile"? A picture would be great. Thanks.
 
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Here is a picture of a "Glock Smile"

This isn't one of mine....mine were much less pronounced and probably wouldn't show up well in a photo. I would (and did) stop before they got this bad. The glock bulge is a different situation than the glock smile. The bulge isn't something I worry about except that I use a Redding GRX die to size it back down. As I understand it, the smile is the brass shearing. Pushing it s little further and it becomes a crack. And Kaboom.

2012-02-16_162750_Glock_Smile.jpg
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That is a nasty picture, and I would immediately toss.
Here is an internet photo that I believe is public domain, that shows the evolution of Glock Chamber support over time.
I have the later, and do not believe the case bulge is an issue after around that time manufacture. However, maximum pressures could make this more of an issue. If not in the 40 SW, then in the 10mm at max loads as OP details.

Picture source: screen capture from: https://www.glocktalk.com/threads/chamber-support-of-glock-barrels.1451518/
 

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Funny - But, my Glock 20 from '94 has a fully supported barrel as indicated in Marco's photo. I've loaded it with 180XTP bullets at better than 1400fps without a brass issue [or issue of any kind]. I'll be the first to admit, 90+% of my shooting with the Glock20 is mild loads in the 1000fps range. But, have no problem pushing the limits with it. I wonder when Glock barrels became "unsupported?" I wonder if this was a 40SW issue which some have assumed exists in the G20 as well. Considering the G20 was introduced when the 10mm was still commercially available in "hot" loads - it would be odd they would take shortcuts on the barrel. I wonder if, due to the shorter case, they undercut the barrel a bit to increase reloading reliability?
 
Looks like on e of my hot loads resized before I got a bulge buster. The Hornady resizing die I had was pushing the case over itself like that. If you reload you might get one. They are cheap and you end up with a Lee carbide taper crimp die as well. I now use that die to crimp in a separate step.
 
Just did some searching. Seems my G20 was made in Austria. Wonder if the under cutting of the chambers started when they began production in Georgia?
 
Strongly suggest you only use new brass for full power testing.

Also, check the diameter of the extraction groove, before and after. It is one indicator of possible overloads.
 
Strongly suggest you only use new brass for full power testing.
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Yes absolutely. The brass I used in the OEM glock barrel at 1180-1200 fps is going in the recycle bin. I would absolutely feel fine about shooting my hot 10mm loads in a factory barrel in New brass. But not afterward due to what I am seeing.

On the other hand, I will reload the alpha wolf barrel brass as lower power range loads next time.

It's like I said, I will push the limit, but I'm not crazy stupid.
1250 fps from a 5.3" barrel is no joke.

I bought 1,000 pieces of starline brass and 1000 nosler JHP's. I burned through nearly 250 during pressure testing and load development. I will load the other 250 at full power, for accuracy testing and sighting in the red dot.
Then load 500 new rounds at full power (1250 fps) and reload what I salvage down around 1,050-1,100 fps for range practice.
 
Now we can cue the safety police comments from the manual limit zealots.
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Ok, I CAN'T BELIEVE YOU DID THAT!!!!!!

;)

Looking at your crony results tracks pretty well with my own experience. I mentioned I stopped at 8.2g when I reached my target velocity (1200), it's interesting that you had the same exact results.

For me, going higher is diminishing returns. If more power is needed, move to your 44 Magnum. I rather enjoy the Nosler HP at 1200, I feel like it's just about right.

Another point of interest: your results very closely track the predicted velocities in Quickload. I have had mixed results with straight wall in QL but it's a great tool for the most part getting pretty close with the correct input.

As for whether anyone needs a 10mm, I have shot max LONGSHOT loads in my M&P 40 that clock a 180 Gold Dot about 1150 fps. That is a smoking load in a 40. I would compare it to the Glock 20 shooting the same bullet about 1300 fps. I've also shot 357 SIG from my M&P 40 at 1500 fps and I am confident that a steady diet of either one would wreck the pistol in a short while. Probably why S&W discontinued the M&P 357 but I digress.....

Edit to add:

QL estimated pressure for 9g LONGSHOT is 52886 psi @ 1262 fps
 
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Accurate #9 powder will get you the velocity you desire with MUCH less pressure.

1,200+ fps using published data (Hornady) and 200 grain bullets... The Nosler bullets will get more speed at safe pressure because it is a little shorter than the XTP.

I have a Glock 40, with a 7 inch KKM barrel, the Nosler 200 gets 1,305 fps in my gun and is accurate enough for 100 yard hunting.
 
I got significant smiles on my brass at 8.4 grains of Longshot, but that was using XTP's instead of the Nosler bullets.

Power Pistol is pretty much identical in performance, being within a tenth of a grain or so of Longshot at all levels in my testing.
 
Accurate #9 powder will get you the velocity you desire with MUCH less pressure.

1,200+ fps using published data (Hornady) and 200 grain bullets... The Nosler bullets will get more speed at safe pressure because it is a little shorter than the XTP.

I have a Glock 40, with a 7 inch KKM barrel, the Nosler 200 gets 1,305 fps in my gun and is accurate enough for 100 yard hunting.
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Can you share your load?
 
200 grain Nosler bullet
12.8 grains of AA #9
Starline brass
CCI 350 primer
~1.26" overall length

If you use non magnum primers, you can bump the powder up to 13 grains... But you will run into compression issues beyond that.

Thats the only reason I use magnum primers... To avoid heavily compressed loads... Fine grained ball powders like #9 don't compress very well at all.

With the 200 XTP..... You'll crush the nose at 12.8 grains unless you modify a seating stem to seat off the ogive instead of the nose.
 
That looks good, I'll give it a go sometime.....

I see Nosler lists a max of 12.4 grains with that bullet, you might wanna insert the disclaimer in your post to be safe.

Thanks.
 
QL estimated pressure for 9g LONGSHOT is 52886 psi @ 1262 fps
Click to expand...

Quickload is indeed a great tool. Pressure and velocity are related for sure. But in other straight walled rounds like my 45-70 and 44 mag I can get the velocities to match what I see on the chroney, but the pressures are way off. I know they are way off because in some instances I'm nowhere near book max and yet quickload has me over max on pressure.

Quickloads issues with straight walled cases is well documented. You can fudge with the start pressures to get it to track velocities in instances where it won't, but unfortunately it was mainly designed for bottleneck cartridges.

Also,
I believe 56k psi in a standard glock chamber would rupture a case, blow out primers, cause caseheads to separate and much more.
 
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