Way over max load, no pressure signs...WTF?

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Ok So I am almost a full grain over max for 200XTP and AA9 in 10mm. I am using a magnum primer as well. Brass looks fine and my velocity is just breaking 1150fps. No signs of too much pressure on the brass, though that isn't always reliable. I only use factory 1f and new brass, but I am still concerned this may be too much. Is it normal to be that far off published data?

Here is the data I started with as taken from Accurate's site. I stopped at 13.2 as I wasn't gaining much velocity after 12.8.

No.9 200 HDY XTP 11.3 1,030 12.5 1,170 37,000 1.250
 
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"Pressure Signs" are pretty much meaningless, except for the one where the gun comes apart. That's why we have load manuals.
 
A lot of manuals are VERY conservative with their load data for the 10MM Auto. Norma produced 10MM 200gr ammo with muzzle velocity OVER 1200 fps, and it had moderate pressure levels.
Double tap sells 1250fps 200XTP ammo.
Some guys from the firing line forums (i think) loaded 200-grainers in 10mm to 1300fps and they worked just fine.
Edit: I did some digging and turns out there is a factory 1300FPS load with 200gr bullet from Double Tap.

Having said that, i wouldnt be pushing it so much. The holes in paper look just as mean from a 1100 FPS bullet as they do from 1300 fps one.
 
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Double-Tap uses proprietary powders for their 10mm line. His loads are top end for sure, yet are safe for the factory Glock Chamber. If I could get his ammo up here reliably I wouldn't bother handloading for 10mm anymore. I should add this is all experimentation, trying to break 1200 fps safely. It's hard.....
 
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"Pressure Signs" are pretty much meaningless, except for the one where the gun comes apart. That's why we have load manuals.
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I do not share that opinion at all.
I have found primer pocket tension to be a very valuable tool in estimating pressure.If the primer pockets are loose after two or three firings,I reduce the load even if the load is not listed as a maximum load in a manual.If there is resistance upon lifting the bolt,or if there are extrusion marks on the case head,I reduce the powder charge.
As well the maximum powder charge listed in manuals can vary by up to five grains from manual to manual in the larger capacity rifle cartridges,and two or three grains in the small rifle cartridges,even with identical components,so which manual is correct for your rifle?
Blindly trusting that all loads listed in all loading manuals will be safe in your gun,is a good way to get yourself into trouble.Even the loading manuals themselves post a disclaimer and suggest that you work loads up from a starting load WHILE WATCHING FOR PRESSURE SIGNS.
 
I get what many consider to be a bad pressure sign no matter what I'm shooting in my 300 win mag. This would be the crater/sides pushed up where the firing pin strikes the primer. It does this in my gun.....doesn't matter what primer......even with greatly reduced cast loads. At the same time, the edges of the primer are not pressed square, but are still slightly beveled. Go figure. Stay within the numbers and you shouldn't have any problems. Get too far outside, and you're on your own.
 
I get what many consider to be a bad pressure sign no matter what I'm shooting in my 300 win mag. This would be the crater/sides pushed up where the firing pin strikes the primer. It does this in my gun.....doesn't matter what primer......even with greatly reduced cast loads. At the same time, the edges of the primer are not pressed square, but are still slightly beveled. Go figure.
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This is actually quite common,usually caused by an oversize firing pin hole in the bolt face.I don't consider it a reliable pressure sign myself.
 
I have fired over 400 rounds of Sierra 190 JSP at 1400 ft/s in a Glock 29 with Storm Lake 106mm barrel with a tight chamber using IMR 800X. All brass have been factory 1f. The only pressure issue I see is a slight mark left on the fired brass by the extractor. I re-use all of the brass for practice rounds following the hot loads (I shoot IDPA with the gun).

The 10mm has a very large amount of room over published info using the right powder. The 10mm forum at GlockTalk has a huge amount of reloading information for different brands of powder. Many loads were posted by Mike McNett (owner of Double Tap). I use his 800X load to get almost 1800ft/s from Sierra 135s in my gun (tight chamber and longer barrel vs stock). I seem to recall that this load in a stock chambered 96mm barrel is in the neighbourhood of 1650ft/s. I check each fired case for signs of pressure. The primers show less sign of pressure than the last batch of factory 175gn Winchester Silvertips that chronoed at 1388 in my gun.

I am very comfortable with the absence of pressure signs with the IMR 800X. I used to shoot 9x19mm IPSC major when the power factor was 175 and learned the hard way to read pressure. I have safely and consistently fired 9x19 to a power factor of 206 in a Nowlin fully supported chamber in a racegun. Just work up slowly and watch for pressure signs.
 
I had a tough time finding it myself. I ended up ordering 4lbs from Higginson. The Hazmat shipping fees make it a bit pricey though if this is all you are buying.

I really want to try VVN105, although I can not find any - and I have tried hard.

The versatility of the 10mm is amazing. I shoot loads ranging from 180gn at 850ft/s up to the the hot ones listed previously and 3 or 4 in between. All loads with the same factory double recoil spring and aftermarket barrel in G29 (required for Canadian ownership).
 
I've had brass bulge out at the base and have blown primers in my attempts to load hot 10mm rounds. If you're not seeing ANY pressure signs whatsoever I wouldn't hesitate pushing it further.

However, I would stick to new Starline brass only, just to be safe.
 
B said:
I am very interested in loads using 800X. I have yet to find any in my travels unfortunately.
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There's an in-depth piece on loading 10mm Auto for a Kimber 1911 in the June 2008 edition of Handloaders magazine.

Here's their data for 800X:

180gr. Sierra JHP
8.5gr → 1,181fps
9.3gr → 1,239fps
10.2gr → 1,311fps

200gr. Speer TMJ
6.5gr → 896fps
7.5gr → 1,019fps
8.5gr → 1,155fps
 
B said:
Ok So I am almost a full grain over max for 200XTP and AA9 in 10mm. I am using a magnum primer as well. Brass looks fine and my velocity is just breaking 1150fps. No signs of too much pressure on the brass, though that isn't always reliable. I only use factory 1f and new brass, but I am still concerned this may be too much. Is it normal to be that far off published data?

Here is the data I started with as taken from Accurate's site. I stopped at 13.2 as I wasn't gaining much velocity after 12.8.

No.9 200 HDY XTP 11.3 1,030 12.5 1,170 37,000 1.250
Click to expand...

The Hornady 7th edition lists 13.2 grs of AA-9 behind the 200 gr XTP as maximum and coincides with velocity of 1150 fps. According to that your loads are within the safe range, but if little velocity gain is realized, you might as well drop back from 13.2 gr load to 12.8 or even 13.0 grs to save your gun from unnecessary battering.

As a rule, when you have matched the velocity of the maximum published load, it is time to stop as pressure must be very near maximum, regardless of the powder charge.
 
Pressure "signs" usually indicate you are well past safety ( primers are unreliable indicators ). One reasonably accurate way to measure safe operational pressure is to measure the pressure ring ( the circumference just ahead of the extractor grove ) with a 1" micrometer. You simply use some factory ammo fired through your gun as a measuring stick. Different types and brands give a good indication and should give similar readings. Then start creeping up your loads from below max and measure the fired brass. You may find that you need to stop below max in some cases or you maybe able to go well over the posted maximum. This gives you a good reference for what is safe and what is not. Different shooting irons will have different results. An increase of 0.0005 inch over the factory load reading is a sign to stop and back off in most applications. These minute readings can only be detected by a precision tool like a micrometer and not a caliper.
 
Boomer said:
The Hornady 7th edition lists 13.2 grs of AA-9 behind the 200 gr XTP as maximum and coincides with velocity of 1150 fps. According to that your loads are within the safe range, but if little velocity gain is realized, you might as well drop back from 13.2 gr load to 12.8 or even 13.0 grs to save your gun from unnecessary battering.

As a rule, when you have matched the velocity of the maximum published load, it is time to stop as pressure must be very near maximum, regardless of the powder charge.
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Something I forgot to mention. I was up to 13.2 for a reason, however when I started to think about Accurate's data I got worried.
 
AA #9 is one of the best powders for beginner 10mm loaders you cannot stuff enough of it into the 10mm case to go over max pressures.

If you can't get IMR800X (I still have over 2lbs) try Blue Dot it is an awesome powder for the 10mm meters accurately and will give you the velocities you are trying to reach.
 
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Really? Blue Dot has been my powder for all my high volume loads. I really do love it though lot to lot variation is significant. Any high end loads you'd like to share with me Camp Cook? I accidently deleted the PM you sent me Eons ago.....
 
I still have 3 1/2 pounds Blue Dot so don't worry about lot to lot changes I need to load up so practice 40S&W loads and was going to check into Blue Dot for them...

You deleted the data and you want me to dig it all out again? :eek:

I'm thinking you need too go back to Glock Talk the 10mm Reloading forum... :p

I just noticed the last time I was there check out the sticky on carbine length data the 4.6" Glock 20, 6" colt Delta Elite & 18.5" Contender barrel data is mine... :D
 
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