Having a problem with vertical stringing, vertical flyers. Here's what I have
Rifle is a trued rem 700 with a 26" bartlein barrel. Mbm beast brake. Hs precision stock, Timney trigger. 300 win mag
Load is adg brass, fed 215, 225 ELDM, rl26 brass has now all been fired and shoulders bumped back .002, .002 neck tension .010" off the lands
So it seems the problem is with multiple powders, bullets. My load currently is 73 gr. Is right over 2900 fps with es of around 20. Yesterday morning and this morning I shot 4 shot groups at 410 yards. 3 went into about 1.25" but had one flyer that strung vertical. It seems I've had vertical stringing issues with this rifle since the start of the new barrel. I thought it was a bedding issue but I've swapped stocks and re bed the rifle twice. I thought it could be a rear bag issue but I've tried two different bags. Tried a bipod and a front rest and still having the issue. What's everyone's thoughts? I have lost faith in the Smith for other reasons so I don't want to take it back to him. Should I have another Smith check it out? Could it be a seating depth issue? I'm at my wit's end with the rifle and don't know where to go. It wants to shoot .25 min groups most of the time but I just can't seem to get it together.
I'm no expert, for darn sure. But...
I've had loose scope mounts cause stringing, but IIRC, they were diagonal strings. If the primer is the culprit, as some have suggested, then the most logical reason would be differences in the MV and your ES of 20 (wow, that's LOW...maybe I suck as a reloader) would suggest not. Sure, timing of the barrel (harmonics) could be a factor with inconsistent ignition, but I would *expect* to get a larger spread all over (circular), not vertical. And an ES of 20 is not indicative of varying MV. Are you running the chrono on the groupings? Maybe some other factor is playing hell with your load and the test MV loads are different than the grouping loads (ask me about a fly that died in my powder throw).
Forgive me if it's already been suggested and I missed it: I would try factory ammunition and see how it groups. You've re-stocked and re-bed the rifle or I'd look for some intermittent contact with the barrel when it's loaded on the rests/bags/bipod. FWIW, I'll say this anyway: on an AR w/M-LOK handguard I had installed a bi-pod mount under the gas block. Like a dipstick, I didn't realize that the 20-30 thousandths of clearance with one of the M-LOK screws was a problem. Until it threw bullets all over the #$%# place. Much frustration later I found that when I set the rifle on the bipod and pulled it down snugly, not tight, the whole thing flexed just enough to cause that one fastener to contact the barrel where it was larger in diameter closer to the chamber. Upon removal of the handguard, I found a shiny spot on the barrel from said contact. DOH! But, still, it was not vertical stringing...stuff was all over.
If the factory ammo does the same thing then switch the scope (after carefully checking, re-checking, and torquing the fasteners (all of them) involved in mounting the scope).
FWIW, I've chambered a few rifle barrels (made AR and Savage and one Rem 700) from blanks on my own lathe myself (no, I'm not a gunsmith). I took a cheap ($35) 6mm LBC or somesuch and cut and chambered it to be an 11.5" 6mm-223. I threaded the barrel and put a Yankee Hill Turbo on it...that's a "dedicated" 224 suppressor and I do not get baffle strikes. That to say, I have a little experience with making finished barrels from blanks. I cannot imagine how the gunsmith could have screwed up that barrel to cause vertical stringing (not by mis-aligned chamber or over-throating, or whatever). I could be wrong...I've been married...twice. However, you might, in as much as you are able to do so, check the barrel fitment into the receiver...is it loose? Try checking the torque of the barrel into the receiver. Still, I'd expect circular spreads, not vertical, but you've had a lot of frustration...might as well check everything.
FWIW, HTH, YMMV, EIEIO.
--HC
