Suggestions for new loads?

[Mosin-Marauder]

I upped the powder of my 7.5 Swiss loads last night by 1 grain. I keep getting about the same results. 2 shots touching and one shot an inch away. All of them 1 3/4" counting the "flyer". Would a heavier bullet be better for groupings? I was thinking 168 grain HPBT's. Your help is appreciated.

It might just be me causing the flyer (probably is) , but all the targets I've shot with this powder and bullet (all with different grains) have grouped the same, So I'm not too sure. Thanks for any help you can provide.

[Brian Pfleuger]

You're looking at max loads there somewhere in the mid to upper 40s, right?

Jumping an entire grain at a time is way too much if you're looking for accuracy. You should be going up no more than 1%, which would be about 0.5gr and I'd personally go with no more than 0.4gr.

On the other hand, you're not exactly talking about a precision bench-rest rifle here so I honestly doubt it matters.

Personally, I'd pick a load (any load) and keep shooting it until I got A WHOLE BUNCH (not 5 or 6 but 20 or 30) of groups that were all close to the same size. It doesn't matter what size, just all the same size.

Eliminate variables. If you're shooting one gun, one bullet, one charge, one distance and one style of target, the only variable is the shooter. Until the shooter can consistently shoot the same size groups without any variables, there's no sense in chasing phantoms of accuracy.

[Bart B.]

Depending on the specific model, those Swiss rifles have different bore, groove and bullet diameters:

http://en.m.wikipedia.org/wiki/7.5%C3%9755mm_Swiss

I suggest measuring yours then using bullets with the same diameter as the barrels groove diameter.

One grain increments in charge weights is good for old military rifles' load development.

If several groups with the same load are not within 10% of being the same size, they don't have enough shots in each to truly indicate the accuracy of that load in that rifle. All other groups fired will be larger than the smallest one.

There are no fliers. All bullets shot go where they were directed by the variables in the shooter, rifle and ammo. When those variables add up in all directions, those bullets land furthest away from the aiming point or group center. If they cancel each other out equally in all directions, the group will be zero; inches, centimeters or MOA.

[Mosin-Marauder]

So, start shooting like 5 shot groups? With the same load?

[Brian Pfleuger]

I would shoot one group until 3 consecutive shots didn't make the group any bigger, whether that was 5 or 30 shots then I'd do it again and again and again until I shot groups over and over and over that were very close (within 10%) to the same size.

Then I'd worry about finding a more accurate load.

Until the shooter can shoot the same size groups repeatedly there is no way of telling one charge from another.

[Bart B.]

I suggest 10-shot groups for each load. Each 10-shot group is many times better than a few 3-shot ones. 20-shot ones are much more representative.

[buck460XVR]

2 shots touching and one shot an inch away. All of them 1 3/4" counting the "flyer".

What was the distance? Was your 'flyer" the first, second or third shot of the group or does it vary? Not every rifle is MOA. Some older military rifles shot ammo with corrosive primers, which may have affected bore.

[Mosin-Marauder]

This was 50 yards off sandbags. K-31's never had corrosive ammo through them, as the GP11 is non corrosive. I'm not sure what shot was the flier, I'll have to get a some binoculars and check the next time I shoot. Though, I think it is the first shot. Don't quote me on that though. The best I've got was 2" at 100 yards with GP11. I would be very happy with 2" at 100 yards with iron sights.

As for shooting the same size groups. I'll load 12 rounds and get some groups at 50 yards and see if they're all the same.

Thanks for your help guys.