superdude

I suspect M&P accuracy is bullet/load specific. Some accuracy comparisons don't show heavy bullets like 147 grain any worse than other weights in a M&P. https://www.shootingillustrated.com/articles/2019/3/23/ammo-accuracy-15-loads-in-three-different-guns/

I'm not familiar with Sig pistols so you folks will have to help me out. I'll use a Glock as an example. A Glock can fire out of battery, or more accurately, when not fully in battery, but there are limits on how far the barrel can be unlocked. As the barrel unlocks it slides down the breech face, and in doing so, the primer slides away from alignment with the firing pin. The firing pin has to hit the primer in a region that will still set off the primer, and that's not too far off center. If the primer has moved far enough away, the off-center firing pin hit won't ignite the primer. I don't know how a Sig unlocks and at what point the barrel starts to move downward. You folks will have to let me know. A Glock barrel starts to slide downward very soon as the slide moves to the rear, so there is a limit on how far the slide and barrel can be 'out of battery' and still have good enough alignment for the firing pin to set off the primer. It's not very far. The out of battery firings that I've seen in a Glock don't produce a bulged case. The only way to know it fired out of battery is to look for the position of the firing pin hit on the primer to see if it's centered or off center. All this of course assumes that the firing pin block doesn't stop the firing pin.

For that type of damage, the bottom of the barrel's feed ramp is extending into the mag well. Technically, it shouldn't.

Thanks.

Here is the original source for that picture: https://www.ssusa.org/articles/2018/1/9/how-to-use-9-major-in-a-short-barrel/ zzt, where at Shooters World did you find this figure? Can you find the link for that? Thanks.

Wet tumbling is not a test of how well the coating holds up when fired through a gun. The proper test for that is firing it through the gun. If the coating stays on then, that's all that matters. I'd hate to see people coming to the wrong conclusion based on how well the coatings hold up when wet tumbling and then make the leap to think it means it will or will not hold up when fired through a gun. It runs the risk of being a spurious correlation.

Yup, Power Pistol is wonderful in the 9mm.

Darn.

What type of accuracy are you (or your friend) getting? Distance, shots per group? Smallest and largest groups? The largest groups would be of particular interest. What barrel brand and twist rate? Preferred primer? Brass? Have you tried different bullets? If so which ones? Their results? Did this come from Bob Marvel? The details might be useful. Thanks.

I think we would all like to know. Thanks.

Few JHP in my experience have slightly hollowed out bases. Zeros are the only one I can think of off the top of my head. philipsinewe, you're right about exposed lead and compensators. A JHP bullet has no exposed lead at the base and thus no lead from the bottom of the bullet is vaporized when fired. Vaporized lead from FMJ bullets with exposed bases will gradually build up in compensators, so most folks with compensators prefer the JHP bullets for this reason. JHP and flat nosed jacketed bullets have a good reputation for accuracy, and in general, tend to shoot more accurately than round nose bullets. Of course there are exceptions to this and it usually depends on which specific bullet one is referring to.

Maybe this will help, though they are with jacketed bullets: https://www.shootingtimes.com/editorial/super-accurate-38-super-loads/326242

determine where it is failing the case gauge, and that will help to understand how to fix it. Use a magic marker, like described at this link: https://www.shootingtimes.com/editorial/reloading-tips-the-plunk-test/99389 Do they fit your gun's chamber?

Don't get carried away. It would simply be like shooting a 45 with factory ammo. Besides, everyone else shooting in the same class would be experiencing the same thing. If 45 Auto-like recoil in Limited division is too much for you, that's fine. No one will force you to shoot in that division. We're getting pretty far off topic. If you want to continue, feel free to open another thread.

Sure, but it's not as bad as you make it sound. Besides, we know how to spring guns to compensate for that. Hammer springs, recoil springs, square firing pin stop.

The recoil of 9 Major or 38 Super at Major power factor does not fit the category of massive recoil. Here's some numbers, all based on a 2 lb gun: 45 ACP, 230 grain @ 850 fps, 8.2 grains of HS-6 (one of the highest charge weights to reach that speed in the Hornady Load manual). Recoil = 6.73 ft lbs. 9 Major 115 grain @ 1518 fps, 10.0 grains of A#7 (my 5" gun) 175 power factor. Recoil = 6.18 ft lbs. This 9 Major load produces less recoil force than a 45 Auto at normal speed. As far as pressure is concerned, we're already loading 9 Major above SAAMI specs (for most powders) anyway. The only thing that differs between an Open gun and a Limited gun is the compensator. Why does it matter if the gun has a compensator or not? It's still the same chamber pressure.

This is correct. The article: https://www.americanrifleman.org/articles/2019/4/23/m1152-m1153-the-army-s-new-9-mm-luger-loads/ From the article: "The pressures for the M1152 and M1153 are 39,700 p.s.i. "In our tests in 1985, XM882 propelled a 124-gr. round-nose FMJ out of the 5" barrel of an M9 at an average of 1273 f.p.s., delivering 446 ft.-lbs. of energy at 15 ft. Using an Oehler Model 43 and firing the new ammunition out of a 4.7"-barreled P320-M17, M1152 with the 115-gr. bullet was at 1326 f.p.s. and 449 ft.-lbs. of energy, while the M1153 clocked 962 f.p.s. with 302 ft.-lbs., both at 15 ft."

Maybe some useful information here: https://www.ssusa.org/articles/2018/1/9/how-to-use-9-major-in-a-short-barrel/

Yeah, that nose looks a little short. Have you determined WHERE the rounds fail? i.e. is the bullet touching the lands? Is the bulged case too big for the chamber? Do the magic marker test to determine exactly where they are not fitting in your chamber/ case gauge. Then we'll know how to address the problem. Explained here: https://www.shootingtimes.com/editorial/reloading-tips-the-plunk-test/99389

So we've heard. But where can we find it here in the USA?

You're welcome! Glad it helped. Ammo is expensive! What happens to be in stock at the moment you search makes a big difference. I tend to check a couple of places when I'm looking for ammo. Saving even a little helps a lot.

If this helps: https://www.targetsportsusa.com/winchester-usa-9mm-ammo-nato-124-gr-fmj-q4318-p-697.aspx https://www.budsgunshop.com/catalog/product_info.php/products_id/53428/winchester+ammo+9mm+nato+124+gr+q4318+full+metal+jacket+50%2fbx https://grabagun.com/winchester-ammunition-q4318-9mmnato-124-fmj-50-rounds.html

A picture or two would be useful if you can swing it.

I've used it a little in a 45 Auto, including some on the low end of the charge weight. Used it with 185 JHP, 200 lead and 230 FMJ bullets. It does seem to provide fairly consistent speeds, based on 10-shot strings - standard deviation of 6-12 fps. Accuracy, with my limited experience, is very good in my 45 with a Kart barrel.

What specific .355 bullet? Name brand, plated, jacketed, ????