Poor Performance in Krag 30-40?

[RPRNY]

I have a Krag sporter with a later barrel that slugs a true .308 bore and .311 groove. Chamber is marginally tighter than the Springfield Armory's somewhat cavalier use of the micrometer. Throat is reasonably long and slugs at .311.

I rolled 150 gr FN (these were lubed Oregon Trail bullets that I de-lubed and sized to .308) and patched out to .312/.313 w/9lbs onion skin. Patch to just above cannelure. Lubed lightly with beeswax/vaseline/LLA. Shot over 25 grs IMR4198. Results were highly inaccurate. It looked like some may have even key-holed.

My guess is that the relatively short bullet and long throat combined to make the bullet somewhat unstable entering the bore. Any other thoughts or advice?

[Nobade]

That one and a half thousandths deep rifling might have something to do with it too.....Kind of hard for it to cut the patch.

-Nobade

[CJR]

Some suggestions:
1. Get a .311 CB and square the base, i.e. chuck in a drill and file the base to a sharp corner.
2. Prepare a dummy round by inserting the CB, nose first, into an EMPTY case so that the OAL is LONG.
3. Try to chamber the LONG dummy round into your rifle.
4. Keep adjusting the OAL until your round chambers in your rifle.
5. That dummy round now shows where the PP must be on your PPCB round.
6. Ideally, as you chamber the PPCB round the PP should contact the chamber's forcing cone. PPCB cannot tolerate "jumping" to the forcing cone.

30/40 Krags have the forcing cone right in front of the case mouth. BUT, you never know if your rifle was free-bored until you use the dummy round. If you find a free-bore and you have to seat the 150 gr. FN too far forward to touch the forcing cone, with little of the PPCB being held by the case mouth, you most likely will need to go to a heavier CB. CB or PPCB held only a little by the case mouth tend to be inaccurate. Why? As the CB gets chambered, it gets "cocked/bent/gets runout". Result? The CB or PPCB starts its journey down the bore misaligned and inaccuracy results. Top accuracy results when the CB axis is identical to the bore axis. This is more critical for high velocity loads which have high RPM.

Hope this helps.

Best regards,

CJR

[RPRNY]

CJR - that's where my thinking was. Krags were throated for that big 220 gr RN and my guess is that the little 150 gr FN would be a challenge no matter what, but I seated them relatively deep to boot. It shoots well with jwords, so I will save the 150 grainers for the 30-30 and work with some big old 225 gr lead that I have.

Nobade - my numbers don't look right in retrospect. That's what I have written in my spreadsheet for the rifle and I do recall slugging it, but .308/.311 does indeed look like a worn out barrel and the bore doesn't look that way. I better slug it again...

[pdawg_shooter]

Try a 311284, patched to the start of the ogive, and seated out so the paper engages the rifling. IIRC, the 311284 was designed with that rifle in mind.

[6.5 mike]

Measure the inside diameter of a fired case, this will tell you how large the throat is & what size boolit you need. My Krags both seem to do better with a longer heavier boolit, DCM cut down carbine & Uberti hi-wall. The lee 200 gr works OK if the nose is big enough. I also have had good results with lee's 312-185, have not tried anything shorter.

[Digital Dan]

That one and a half thousandths deep rifling might have something to do with it too.....Kind of hard for it to cut the patch.

-Nobade

Have to wonder if those numbers are correct and if so have to doubt is would shoot anything well.

[Outpost75]

Most US Krags I have slugged run large and the diameters of the freebored section also run large. I have always used bullets intended for the .303 British in mine, #314299 cast of wheelweights, loaded as-cast and unsized, crimping the GC in a .313" die, and either 15 grs. of #2400, 23 grs. of 4198, or 26 grs. of RL7 have worked for me.

[smkummer]

As above, I am running Lyman's new 311644 190 grain bullet sized at .311 to seat a gas check. Very accurate out of my 1901 made 1898 rifle. 1800 FPS with a charge of 2400. I won't change a thing. In fact all of my 30 cal. guns that I am shooting of late such as Win 94 30-30, US 1903A3, Yugo SKS and the Krag, get shot with .311 diameter lead bullets with gas checks and the results are as good if not better than factory Jacketed bullets.

[RPRNY]

May I remind the well intended posters who have provided helpful advice utterly irrelevant to paper patching, the forum in which this post was made.

I have found several very suitable gas checked bullets, the best of which has been the 311284. But this is about paper patching, thanks very much.

[303Guy]

That one and a half thousandths deep rifling might have something to do with it too.....Kind of hard for it to cut the patch.

-Nobade

I have a rifle with just such a problem. It takes enough powder charge to disintegrate the patch. In my case I had to increase the charge when the bore polished up. Other than that, I think the longer and fatter the boolit the better.

[RPRNY]

So, life got in the way, but I have finally had the chance to do something about this. Today I loaded 40 of these: 225 gr FN GC patched out to .3125 / .313". They chamber fine although I had to drop COAL to 3.015 to get them to seat so that they were touching the lands but not jammed in. I like the design. Have several groups loaded with 22 grs IMR4198 up through 25 grs. Let's see how these do.

[Kragman71]

Hello,
II spent a L O T of time trying to get a decent group in my Krag, with an assortment of bullets; including 3 different custom molds.
Nothing worked.
I switched to the 30/30 Winchester and struck Gold.
; veryeasily.
Cood Luck
Frank

[RPRNY]

Well this try was also a fiasco. These big fellas were keyholing at 25 yards! Seated too far into the lands? Too long to stabilize ? No idea. Very frustrating.

[Dan Cash]

Your picture looks like ou have quite a crimp on the case. Try only removing the bell in the neck. Also, if your paper patch is not engaging the rifling, lay the patch farther forward.

[barrabruce]

Where the lands touched the side of the bullet is where you want to patch too.

You could use these half wraps if the paper is locked down real tight on the boolit and the nose rubbed with lube to gc velocity for alloy.

I have experienced 1/2 jackets and can tell from experience that they can work ....but it is so easy for the paper to catch and fold/ tear back and then you have trouble....unless they are locked in to the core.

You leave a bit of lead and the next shot goes off also.
If your throat is a large or has freebore you can get gas cutting and pressure running up the bollits befor they are in the barrel and sealed.

A 100% load with slow powder seems to work better as I think the base gets pushed and seated before all the powder ignites. adi 2209 or something like that



I tend to use darcon in my gun....not this cartridge thou and leave a good tail on the patch. Sized down which forma a sort of wad/gasheck on the base.

Some playing with darcon and a bit of grits in the case neck is what they used in the old days before gas checks to seal and protect the bullet.

Having said that I have never tried it.



Hope it helps
Barra

[Char-Gar]

A couple of points as I am somewhat familiar with Krag rifles.

1. You numbers don't sound right to me. I have 4 Krag rifles and they all measure .3015 - .302 in the bore and vary from .308 to ..312 in the groove. It is you .308 bore number that sounds really funky to me. Every Krag rifle I know of has throats/freebore larger than .311. Most often several thousands larger than that.

2. Know nothing about paper patch bullets.

3. Like Outpost75, I have had best luck with bullets .313 or .314.

[RPRNY]

Well I got a chance to re-slug today and check my numbers. My recollection was off. The bore slugs .301/.302 and the grooves are more or less .311. Throat seems @ .313. The barrel is not a Springfield Armory "in the 30 cal area" original but an unmarked addition from the time it was sporterised: early Sixties, my guess. The barrel was truly filthy. I am pretty fastidious and clean well after every time I shoot, so I can't explain this but it may have been a contributor to the poor performance.

I appreciate the advice to try patching up to where it touches the lands and to back off on the crimp. Very good points that I will employ for my next attempt! Thank you all for good advice.

Loaded a bunch today with H4350 at about 95% load. Cut wider patches and brought them up to where the nose is touching the lands and backed off the crimp as suggested. Won't get a chance to shoot the until next weekend. Will advise. Again, thanks for the help.

[RPRNY]

Much better. I need to back off the 4350 as I am getting some lack of combustion, so will try 38.5 grs but this is much more promising.

[303Guy]

I'm not sure what you mean by "back off the 4350 ... some lack of combustion". 95% load under a 225gr boolit sounds a little high for the Krag (not too sure). What did the primers look like?