Due to the COVID 9mm ammo shortage, I've been shooting firing range reloads. I've never had any issues before with my P320 M18 using newly mfg ammo, but I did experience a couple stovepipes with this range reload ammo the last time at the range. When looking at the Sig FAQs, I noticed they recommend only SAAMI ammunition (and no reloads). Is pretty much all new 9mm made to SAAMI specifications, or are there differences from manufacturer to manufacturer?

Perhaps more of an authority will chime in, but as I understand it, SAAMI establishes dimensional standards, but chamber pressure is only a maximum value. Although most of us can’t measure chamber pressures, it’s obvious that velocities which are largely dependent on pressure (although not exclusively) vary significantly among manufacturers and specific loads. Keep in mind as well that in 9mm Luger/Parabellum, SAAMI spec ammunition can go up to +P loads, but even that is a maximum. I have chronographed ammunition rated by the manufacturer as +P whose average velocity was at the upper end of standard pressure loads’. I believe all American manufacturers load to SAAMI or NATO specifications (the last time I checked, SIG also approves NATO-spec ammo).

“Stovepipe” failures to eject are usually due to slow slide velocity, and if that’s not due to other factors like inadequate cleaning or lubrication, or a too powerful recoil spring, it’s normally the fault of underpowered ammunition. Commercial reloaders often skimp on powder charges, evidently to save money, and what you describe can be common with their products. Failure to resize cartridge cases properly can also contribute to the problem.

Thank you for the reply. A lot of good info there.

You’re welcome, but in thinking about this statement I realized that it’s not always true:

quote:

Originally posted by sigfreund:
I believe all American manufacturers load to SAAMI or NATO specifications ....

Some ammunition does not have a SAAMI specification, and the most common (I believe) are +P+ loads in 9mm Luger. SAAMI does not have a spec for 9mm +P+ and therefore something like the Winchester 127 grain +P+ load, while not excessive or dangerous in a modern gun in my experience, would not be approved for use by SIG. The same would be true if a manufacturer marketed something they called a +P load in 40 Smith & Wesson. There are only a limited number of +P loads for which SAAMI specifications exist, and none for +P+. If I wanted to follow SIG’s guidance about ammunition, I would only use the loads for which SAAMI specs exist, and in the case of 9mm, that means nothing labeled +P+.

Another thing to keep in mind, though, is that without a SAAMI specification, a designation like +P+ or +P for 380 Automatic, 40 S&W, 44 Magnum, or countless other cartridges means anything the manufacturer wants it to—or nothing at all. A company could develop a 357 SIG load that drove a 125 grain bullet at 1000 fps and at less than SAAMI pressure spec and despite the fact that it would be a very mild load for the cartridge they could still call it +P or +P+. They wouldn’t be violating SAAMI rules (as far as I know) because there is no SAAMI spec for +P or +P+ 357 SIG.

Most range of shop supplied reloads tend to be loaded on the lighter side to get more loads per pound out of powder, hence the stove pipes.
Every gun company in existence today has a squad of lawyers on retainer and every owners manual of every gun maker in at least the last 40 years will state no reloads.
Bottom line a proper specification/assembled reload is perfectly safe in any gun.
An out of specification/improperly assembled reload is not safe in any gun.

I would expect more with reloads sold by a gun range, better tested. Just like with factory ammo, any ammo can have problems in a particular gun.

I can see reloads on the milder side, but they still have to cycle reliably. I guess that’s ammo to cross off your shopping list.

Cheap range ammunition tends to use dirtier powder, too; cleaner burning powder is more expensive. Dirtier powder, especially in a well lubricated pistol, can lead to more crud in the weapon, under the extractor claw, etc.

Lower power rounds do not fully expand the brass along the walls of the chamber: it's most noticeable when examining the ejected brass. If the brass looks blackened and dirty, there was blowback occurring in the chamber when the round was fired; the chamber pressure rose, the bullet entered the forcing cone in the barrel, and some of that pressure blew back past the brass; lower pressur the or escaping pressure further lowers slide velocity and bullet velocity, and makes for a dirty chamber, breech face, extractor, etc.

Brass which hasn't been fully resized can also contribute to the problem, as can brass in which the flare hasn't been taken out of the case, after the bullet has been seated, when the ammunition was made. That can cause additional friction in the chamber, difficulty extracting, and reduce velocity, and add to uneven or unreliable extraction.

Some ammunition can also contribute to the problem; some wadcutter ammo or ammunition with sharp shoulders can have feed issues, but can also impinge on the brass coming out, in some pistols.