I posted this under an old pistol thread, but realized it might be better addressed here.

Developing 200XTP loads for my 10mm Auto S&W 1006. Had given up on 800x because I was getting very erratic chrony readings, but just realized that my chrony battery may have needed changing, possible causing me to abandon 800x too soon. I had read an article (lost it, but I think it was in some handgun mag) on 10mm/800x that featured 180 jacketed bullets and if I recall correctly they pushed 1gr+ over IMR's data. I use PR measurements, velocity change, and visual inspection to determine where I am w/pressure and when a load is becoming unstable. I have determined that .4281" (determined from DoubleTap180GD=34,900psi, TexasAmmo 200XTP, and my 200XTP/12.5grAA#9=37,000psi loads) in my 1006 is the max PR that I am comfortable with. IMR max load data is 7.8gr200XTP=32,500psi(low psi for a max????). I have fired 8.8gr of 800x @ 1130fps and been shy of my max PR. Does anyone have experience with 800x/200XTP's in the 10mm and/or can calc with quickload when I will be at 37,500psi max(800x/NewStarlineBrass/Fed150/200XTP's)?

Thanks,
Deke.

The IMR sits says "Hi-Skor" 800-X 7.8gr 1130fps 32500 psi

You are talking about 1 gr. extra which would be a 13% overload.

I have found the threshold of case bulge in a 10mm 800X 26% overload with a Glock 20 with feed ramp case support .306" from the breech face.

But with a Bar-Sto aftermarket barrel with feed ramp case support .224" from the breech face, I have found the 800X 200 gr threshold of case bulge to be at 82% overload.

AA#9 is the same powder as Enforcer, and I find that the max that will fit with 200 gr is a 26% overload, and I have shot that in the Bar-Sto. It is a ball powder with a high bulk modulus, and there is not much compression possible without deforming the bullet.

Quickload does not list 800X.

tnekkcc,

If I understand you correctly, 9.8gr 800x is max with a Glock 20 stock barrel. I am not sure where my feed ramp case support is on my S&W1006 (I am primarily a long gun guy, can you help me figure this out?).

The published AA#9 max load is listed as 37,000psi (just 500psi short of max). The published 800x max is 32,500psi (a full 5,000 short of max) so I am more comfortable pushing this one, but will hold tight to 12.5gr of AA#9, and will not push the 800x past my max PR of .4281".

Thanks for all your help,
Deke.

Take the barrel out of the pistol.

Put an empty brass case in the chamber.

Scribe a line on the brass with a needle to outline the shape of the feed ramp.

Hold the scribed case in one hand and a dial caliper in the other. With one of the jaws on the base, adjust the calipers until the other jaw lines up with the scribed line.

The reading on the caliper is distance from the breech face to the feed ramp case support. Actually the tilt of the calipers makes it a tiny bit larger and the slop of the case in the chamber when the gun is assembled makes it a tiny bit less.

Anyway, .180" is perfect, as that is the thickness of the web of 10mm brass. Any more than that is equal to the length of unsupported thin case wall.

My guess is that your 1006 is better than a Stock Glock, but not as good as a Bar-Sto barrel.

When you work up a load, put a towel over the pistol to catch the brass. Examine the brass for a case bulge. If you ever see any case bulge, stop the work up immediately. Reduce the load 1 gr.

Here is a very exaggerated case bulge. Look for the first sign of a line or guppy belly with an eye loop at the range.

Don't keep going until it looks like this.


And wear eye protection.

tnekkcc,

Looks like we are both right on the money. 9.8gr of 800x (26% overcharge) produced a PR of .4781" which is the same as 12.5gr of AA#9 and the hottest factory ammo. 1242.5fps with the 200XTP producing 685.5ft# energy at the muzzle . 589.2 @ 50yrds exceeds CO hunting requirements and 516.7 @ 100yrds exceeds WY hunting requirements. Can't wait to see how it performs on game.

Deke.