Need help with bullet set back

[Dudedog]

I loaded 40 rounds of RMR 124 gr FMJ loaded to 1.12” col and 4.2 and 4.4 Win 241. It function good on my 2 gun but Springfield 1911 have a good group, I think I like it.
I also load 20 rounds of RMR 115 gr FMJ to 1.115 COL with 4.4 win 231

W231 for both? (There is a W244 no 241 guessing 231 w/typo)

I don't shoot a lot of 115s (my guns prefer 124/125s)
I think the 115 load might shoot better with a bit more powder
Hodgdon data
115 GR. SPR GDHP Winchester 231 .355" 1.125" 4.7 1075 25,300 CUP 5.1 1167 28,100 CUP
Lyman list Start 3.5 MAX 4.9 with a different 124 JHP
I would load some of the 115s at 4.6 and 4.8 and see if that load works better for you.

Both 4.2 and 4.4gr look pretty good with the 124s..
As far as the different pistols in 9mm I have a Taurus PT99, Sig P226, XD Sub-compact, XD compact, and two Springfield 9mm 1911s.
They very seldom agree on what they like best, however I have found that a load that shoots well in one tends to shoot well in the others


If you are testing for accuracy using a rest helps because it takes part of you the shooter out of the equation.

 

[243winxb]

The mark comes from a raised part of the bolt face/slide area? If i remember correctly? There was a thread about it before, but cant find it now. Was 45acp, i think?

 

[NMexJim]

Those primers reflect about a mid-range load. They do tell you that you can load higher. As you get hotter, the primers will flatten out more although basing pressure by primer condition alone can be misleading. At some point off in the future, it's nice to have a chronometer to measure velocity as another indicator of pressure.

I think everyone on this forum will say that starting low (well, midrange anyway) and working up carefully is the way to go. It's a survival basic.

As a point of discussion only, 9mm is one of the four cartridges for which SAAMI has tested +P loads. You can check your owners' manuals to see if your firearms are rated for +P ammunition. Regardless, both the Springfield and the CZ are well designed, strong guns.

Probably all of us have run higher pressure loads at some point for one reason or another, but in the long run, they can be hard on the driver and the equipment. Personally, I'm happy now training with a load that feels close to my carry ammo and shoots to the same point. Matching to carry ammo with a degree of accuracy can be an accomplishment in itself.

 

[PO2Hammer]

Ejector mark.
Normal for many guns.
It's generally considered a bad idea to load higher based on primer appearance.
You may have room to go up, but don't read that by the primer.

 

[ballman6711]

Ejector mark.
Normal for many guns.

The mark is made because the breech face is not machined completely/perfectly flat. When the brass slams back into the breech face the imperfection marks the soft brass, leaving the mark you have. The breech face can be cleaned up which would eliminate the marks on your brass, but it won't hurt anything and as has been stated is normal for many guns. My Kimber 45acp does the same thing.

chris

 

[Blue68f100]

The mark is from the breach face provided it's opposite the extractor. This is common caused by the mfg process. It can be cleaned up using a scrapper but your is considered very light compared to many I have seen. Like said will not hurt anything as is, and give you an identifying mark that it was fired in your gun.

 

[snnewbie2020]

Thank you Ballman6711 and Blue68f100.