With my 'new' batch of 3.26g FMJ .222 Rem Privi ParTizan I am rather poor, open groups and, when firing 10+ rounds in succession, significant horizontal stringing (like a vapour trail to the right!).

The rifle, a mid weight barrel Kimber 82, I think, groups slightly under half an inch with Sellier and Bellot.

Has anyone else experienced something similar? Another shooter at our rifle club, with a Sako, told me he has had similar horizontal stringing and consistent 4 or 5th shot fliers. With this in mind, and given Privi partisan is fairly cheap ammunition, I wondered whether it was s manufacturing QA/QC issue?

I have had great luck with PPU in a lot of calibers and brass last forever..

Stringing is generally one of two things, most of the time its a bind in the tang, sometimes its side pressure in the barrel channel, but be careful here as side pressure in the tang can cause side pressure in the barrel channel so always releave the tang on the opposite side of what appears to be pressure in the barrel channel or you will end up with a a big gap in the barrel channel when your done....

For stringing I would look for rifle problems which may be more pronounced with certain ammo. My Montana was "almost " free floating When I corrected that groups were half the size.
Designed for a fine accurate gun the QC man sometimes looks the other way ! They can be corrected !

Thank you for the replies. With S&B ammunition, the Kimber does circa 3/4 inch groups at 100 yards. On the day when tested, those groups were about 2 inches to the left in a nice tight cluster. The Privi Partizan, however, was producing open groups circa 1.5 - 2.5 inches plus the dispersion of shots to the right.

I am going to give it another try with both makes of ammunition and hopefully an almost windless day. I wonder if there was some wind blowing through the gaps at the end of the range on that day which caused the shift left / right.

As long as the Privi Partizan groups reasonably well, about a central point, it will be good enough for my purposes. I normally use the rifle for the running deer targets.

My 270Win gave me horizontal stringing using RE22 powder and a 130gr TSX. It also gave me 3,200fps+ out of a 24" barrel.

I tried 4 different types of brass, primers, seating depth, I even took out the old glass bedding and re-bedded the rifle, and could not cure it.

Switching powders solved the problem, both IMR4350 and H4831SC shot great, but I did lose a bit of speed.

Ray was pretty specific but horizontal is generally bedding.
I'm not a gunsmith so compare my recommendations to others but.... With the action screw tight I'd loosen the rear, then watch for movement when loosening the front. It shouldn't move.
One thing though before we start removing material and bedding it. How tight on which screw can sometimes cause issues. It's because of the bedding but with the screws tightened the way your gun likes you can get by until you're ready to tackle it.

I had a Win 70 that shot best with the front screw tight and the back ones just snug enough to keep them from falling out.

horizontal stringing can be from ignition characteristics of the powder/primer combination.
this usually shows up as velocity variations and vertical stringing.

but in this case I think you got the barrel touching the stock somewhere.
that's generally indicated by the shots going off in a 45* or so angle.

quote:

Originally posted by Lamar:
horizontal stringing can be from ignition characteristics of the powder/primer combination.
this usually shows up as velocity variations and vertical stringing.

but in this case I think you got the barrel touching the stock somewhere.
that's generally indicated by the shots going off in a 45* or so angle.

WTH are you saying? I'm confused just trying to read this.

He is saying primers or the wrong powder charge or the wrong powder charge can create your problem, and it certainly can..

I will say 99% of the time its the tang that's tight on one side or the other and that pushes the barrel to the opposite side against the barrel channel..To many folks start inletting the barrel and the barrel keeps moving until you have a seriously big gap, when a small amount of scraping on the opposite side of the tang would have fixed it and you couldn't tell any work had been done on the gun, that's a good thing btw...A little lamp black on the barrel and tang tells the story, wacking on the wood with guess and by gosh is butchery at its best..

quote:

Originally posted by Lamar:
horizontal stringing can be from ignition characteristics of the powder/primer combination.
this usually shows up as velocity variations and vertical stringing.

but in this case I think you got the barrel touching the stock somewhere.
that's generally indicated by the shots going off in a 45* or so angle

So ignition characteristics that generally cause vertical stringing causes horizontal stringing, and the bedding issues that look like horizontal stringing is actually @ 45*?

I won't argue the point made about the tang pressure at all.

Differences in ignition are reflected in velocity changes and generally higher deviations in velocity reflected in vertical stringing. Without getting into barrel harmonics, or stresses it's rare to see horizontal stringing from high deviation in velocity IME.

When I see random patterns, horizontal patterns, holes anything other than vertical I'm inclined to start with bedding issues. If issues look vertical I look at changing primers before much else.

I probably have a lot to learn but I don't get how high std dev is going to cause horizontal stringing without bedding issues. Nate

Assuming that all things are good with the rifle you can also get horizontal stringing from your shoulder position behind the rifle. As your group progresses your right shoulder gets a little further back on the bench from recoil or anticipation of recoil and your groups start moving to the right (assuming you're a right handed shooter). Not saying this is the problem but something else to look at.

looks like a couple of words got lost when I posted the first time

horizontal stringing can be caused by ignition issues.
vertical stringing is caused by velocity variations.

a string that goes out at 45* is generally the barrel touching something and it 'walks off' as it heats up.

I always check my scope mounts if a rifle all of a sudden starts doing strange things

quote:

Originally posted by p dog shooter:
I always check my scope mounts if a rifle all of a sudden starts doing strange things

Yes and stock screws too.

When a rifle strings some Privi FMJ ammo and shoots something else into 1/2" its time to look at the ammo.