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View Full Version : Well that's odd... what happened?



jonk
08-03-2009, 09:33 AM
I've slowly been getting into paper patching. I've had good results in my Enfield and am working into it on an 1898 Krag.

I started with a Lee 185 gr .312, sized to .309. Double wrap of printer paper to just overlap the base and go just past the ogive of the bullet. Let dry overnight, then sized to .309 again. Bore in the gun measures .3085.

As an aside here, pushing the patched bullets through my lee sizer die scrubbed or sanded a lot of leading out of the sizer.

Anyhow, back to the story. Loaded over 35 gr of IMR 4895. Half of the bullets shot high and right but in an ok group, but a few fliers went down into the mud well short of the target. The others were into the backstop but also low and to the left. There was no bore leading to speak of, though the tube did look shinier after 15 pp bullets than before, so the patch wasn't failing in the bore. All the bullets had good fillout and looked fine otherwise.

I'm wondering if direction of wrappign could cause this? I was experimenting with some going each direction, though if they shred off after the muzzle it shouldn't really matter.

What do you think? I haven't seen this with my Enfield so I'm stumped.

docone31
08-03-2009, 09:48 AM
It seems they might be a little slender. Perhpas .0005 off.

pdawg_shooter
08-03-2009, 12:52 PM
For a .308 groove you might try sizing .301/.3015, wrap with 2 wraps of 16# paper. Lube and size in a .309 die for .310 finish diameter.

yeahbub
08-03-2009, 02:22 PM
Are they soft enough top obturate all the way up to groove dia? A sized dia of .309 in a .3085 bore gives .0005 interference, which should center them nicely. How much bigger is groove dimension? I once played with a Mosin that had a .316 groove dia and relying on obturation was the only option since the chamber wouldn't allow a boolit larger than .313. Once I got it right, it did remarkably better.

The direction of the wrap may matter if the angle agrees with the rifling rate and is parallel to it. Any gap between the ends may allow a leak during it's time in the barrel possibly cutting the patch and gas-eroding the boolit. As a rule, I wrap mine so the slant is opposite the rifling causing it to cross lands and grooves for a sure seal. Another way to keep the seam from parallelling the rifling is to cut the patches with square ends. Unless the grooves are unusually wide (two-groove rifling) the seam will cross a land and be sealed.

jonk
08-03-2009, 05:39 PM
They are ACWW.

I might try sizing them to .310 next time or even .311.

I also have a push through .301 sizer for my 7.35 Carcano. It about obliterates the lube grooves if a 308 is pushed through but that's ok. I might try that and patch without sizing after.

The Enfield was so much easier... start with a .308 bullet, double wrap left it at .316, no sizing needed for the .3145 bore. Smear some JPW or LLA if desired on and done.

Digital Dan
08-03-2009, 06:41 PM
My opinion FWIW, the less sizing done on bullets the better, patched or GG. Direction of wrap matters. You want the paper to be wrapped in the same direction as the twist. Dunno where that load stacks up pressure wise, but if it's mild, jack it up a bit.

bcp477
08-03-2009, 06:41 PM
You said that BORE size measures .3085" in your Krag.... is that correct ? BORE size...not GROOVE size ? I thought that Krags were (supposed to be) .300" bore size.....and .308" groove. Am I wrong ? If your groove size is larger than .308 (or .309, for that matter)....and you are shooting PP bullets at .309" finished dia., then I see why you are not getting consistent results. Unless your bullets are dead soft, i.e., pure lead basically, they won't obturate much with smokeless powder. Whatever your groove size really is, you should be at that number or up to about .001" larger, with your finished PP bullets.

Now, if you MEANT to say that your GROOVE size is .3085"....then .309" finished dia. should be OK (though no guarantees). If that is the case, then your problem is likely something other than bullet size..... i.e., bullet weight, incompatible design for your particular rifle, actual bullet weights varying too much, wrapping issues, etc. Finding the problem will simply require experimentation.

beemer
08-06-2009, 09:21 PM
I have never worked with a Krag but have shot a 303 with PP a good bit. Accuracy was not good with light loads, I use the starting load for jacketed bullets and work up a few grains. For some reason my 303 needs a little bit of dacron even with PP.I don't know why but the groups open up without it. I don't use much .4 or .5 grs. at the most. Sizing larger might help and using thinner paper would make sizing less of a problem, I use .0015 tracing paper.

beemer

jonk
08-10-2009, 09:39 AM
Yes, groove size is .3085. Bore size across the rifling is about .301. So the .309s might be fine but might be a little loose.

It's not somethign I'll have a chance to repeat for a few weeks but will let you know how it turns out.