Fast powders harming semi-auto pistols, especially SIGs?

[judaspriest]

The other weekend I borrowed a friend's AGI Armorer's Course on Sig pistols. At the very end the Robert Dunlap mentions that fast-burning powders are quite harmful to the semi-autos, particularly to Sigs. According to Mr. Dunlap, the locking block gets deformed by repeated use of fast-burning powders in a SIG.

Have people seen any evidence supporting this suggestion? I was considering buying some Bullseye (2nd fastest in Lee loading manual's comparison chart) but now I am concerned...

Thanks,

JP

 

[DEDON45]

I've never heard that; but I do stay away from the faster powders (like bullseye) because a double charge is hard to detect with them... I prefer to use powders that nearly fill the case (up to where the bullet seats), and would show a double charge as an overflowing case (I use HS-6 in my .45ACP and H110 in my .44Mag) ... a double charge would tear up a pistol, Sig or otherwise...

 

[RyanM]

Meeehh? Note to self, take everything Robert Dunlap says with a grain of salt

 

[Mt Shooter]

I have been using bullseye for years. I load 45 and 40s&w with it without a problem. A fast burning powder like bullseye is recommended for the 45 apc. As far as a double charge goes, yes it is possible, always look in the case to insure it looks correct visually.

 

[FieroCDSP]

Higher pressures through many loads can harm the locking block on almost any gun, but I've never heard of faster powders being an issue specificly. The SAAMI listed pressures are considered safe in most guns, and a lot of those loads use fast powders. In fact, a fast powder is usually the most economical, as you use less of it for a given pressure, hence why Titegroup and Bullseye are so popular.

+P and +P+ ammo can beat the snot out of a gun pretty quick, but Max-pressure loads, as conservative as SAAMI sets them, shouldn't cause much undue wear to a well-made gun. A cheap gun might be a bit more susceptable to it, though. A Sig, being a decently made gun, will handle most max-loads. I'm sure the warning was put in there to disuade people who would want to run +P in it all the time.

 

[strat81]

I have to imagine that fast powders are among the most popular, for whatever reason. Bullseye, Titegroup, Red Dot, and AA#2 are some of the most recommended powders for 9mm and 45acp, both of which are common calibers for Sig pistols. If there were problems we would've heard about it a long time ago.

Keep it to published loads and you'll be fine.

 

[evan price]

I've run literally thousands of rounds through my various Sigs that I handloaded with Titegroup. No issues I can see and I am pretty good about cleaning and inspecting.

According to the Hodgdon powder speed chart:

#1 Norma R1
#2 Winchester WAALite
#3 Vihtavouri N310
#4 Alliant e3
#5 Hodgdon Titewad
#6 Alliant Red Dot
#7 Hodgdon Clays
#8 IMR Hi-Skor 700-X
#9 Alliant Bullseye
#10 Hodgdon Titegroup

 

[Slamfire]

I would say slow burning powders would "hurt" an autopistol more than fast burning.

I can't think of an autopistol that is not a short recoil mechanism. That is the barrel and slide move rearwards for a time, then you get unlock. (Well now I can remember some strange Austrian pistol that was gas operated)

That movement period is called the dwell. Dwell is there to allow unlock to occur at a safe pressure. Unlock occurs in these things when there still is residual breech pressure. Some pressure is helpful in popping the case out of the breech, and accelerating the slide.

Slow powders have a higher breech pressure at unlock. Then the slide gets accelerated even faster.

Increased slide speeds bang up the receiver and the slide. In the case of a P-1 or M92, the lugs hit the frame at unlock.





No, I don't think high pressure at unlock is a good thing.

In my opinion, the best powders give a short, fast, kick to the mechanism. I like Bullseye, w231 in autopistols. Blue Dot was a failure, beat the heck out of my pistols.

 

[Jim Watson]

Read the fine print in Accurate Arms load data and they warn that fast AA #2 may not cycle European 9mms. Kind of opposite from beating them up, eh?

All those years the Army had .45 ACP loaded with Bullseye or the comparable DuPont powder really banged the guns up didn't it? Or not.

 

[Werewolf]

I've got a Sig P220. I've tried a number of powders in loads I developed for it. I've tried (fast burning to slowest) Titegroup, HP38, AA#5, and HS-6.

AA#5 and HS-6 are far too slow burning for the 4.25" barrel. AND they really really sucked for accuracy with a 230gr fmj bullet.

Titegroup was better. HP-38 was the most accurate with a load duplicating military velocity of 830FPS with a fmj 230gr bullet.

On the other hand my full size 1911 likes AA#5 best.

And wierdest of all my 3" barrel Kimber Ultra-Tac II also likes AA#5 the best. I would have thought that with that 3" barrel it would like TG or HP-38 but noooo... it loves AA#5 and shoots pretty darn good with HS-6.