Schrodinger's headspace - a problem that isn't?

[psteinmayer]

Looking at your data Eric, it looks like some of the manuals I consulted were VERY conservative! Do you think I ought to break em down and bump up the charge? I applied a slight crimp (LEE Factory Crimp Die), so I'd need to remove that crimp. Or... I could just shoot them and then reload them hotter.

Hmmmm... what to do?

[Parashooter]

Shoot 10 or 20. If they group, obturate, and form OK, use the rest. If not, pull down, neck size, reload. Maybe discontinue crimping for SMLE - unnecessary variable if properly sized.

Looking at Hodgdon online data, their Max load is only 43600 CUP - well below SAAMI max 45000 CUP. Pretty conservative.

150 GR. HDY SP
H4895
Starting: 36.0grn 2,447fps 40,300 CUP
Maximum:40.0grn 2,627fps 43,600 CUP

Note that QL estimates are piezo "psi" (SAAMI max 49000 psi).

[psteinmayer]

Hogdon online data was one of my sources! Ok, as soon as I can hit a range, I'll give em a whirl and see how they group. I think that the next ones I load I'll bump it up to 40 grains.

Thanks very much

[Parashooter]

Just for grins, take a look at Hodgdon online .30/40 data with H4895 and 150 grain bullet. Should give an idea how conservative their .303 data might be.

(Usable volume of .30/40 case is about 1 grain more than .303, thanks to longer neck and normal OAL of .30/40. Load to same OAL and there's almost no difference.)

[carbon outlaw]

I was just checking rim thickness it seem to be .059 to .063 on a verity of brass ... I use the trick of putting shims on the bolt face and adding them until the bolt closes tight ..then you just measure to get how much head space you have ... here is something I think is really funny ... I purchased a barreled receiver and i thought ill check the head space since i have it all pulled apart and guess what the put a new barrel on the action but they never reamed out the chamber or set the head space so the brass will not chamber at all stickies out about 1/8 inch so I my not be building a new sporter krag after all ...

[FredC]

Carbon Outlaw, on the loose barrel it looks like the chamber is OK? That is for demo purposes, correct?

The barreled action does look like the case is sitting proud. If it were mine I would try an EMPTY case with black Sharpie marks all over and barely tap it in a little, then tap it out through the barrel. It does not need to be forced, just get it stuck a couple of times so you can tap it out with your palm. I would expect that you will see the marks on the brass were your interference is coming from.
If it is actually not finished reamed it could be finished by hand without unscrewing the barrel. See the last item or 2 in my thread:
http://www.kragcollectorsassociation.org/cgi-bin/yabb2/YaBB.pl?num=1450216996/15#15
If you can borrow or rent a Krag standard reamer you can use my brass extension to drive it. My reamer is 35/40 and I just sold it to a fellow KCA member who is building a sporter with a 20 inch barrel. He is supposed to be taking pictures to share here later.
.
There is a possibility you just have some dry crud stuck or glued in the chamber, if so you could hack saw and file a case in half and use it like a "cleaner" reamer, just need a way to rotate it. If you put 1/4 -28 threads through the primer hole my driver could be used to turn it.

Would sure hate to see you stop on your project.

[butlersrangers]

Carbon Outlaw - Regarding your problem barrel:

Does it appear to be an 'altered' Springfield Armory made Krag barrel?

An altered 1903 Springfield barrel?

Or a commercial barrel?

(Springfield Armory made Krag barrels were completely finished and chambered, before assembly onto action).

[carbon outlaw]

it is a aftermarket barrel ... it looks like a barrel you put on then cut your dove tails or add sights and then finish by hand reaming the chamber ... looks like they never reamed it ... probably the reason why i got it so cheep ... I have seen reamers on ebay for sale and lots of YouTube videos .. got lots of time to figure it out ... thanks for your help ...

[FredC]

There is such a thing as a roughing reamer to get a chamber almost to size. They would mainly be used by some one turning out dozens of the same barrel, to ease the wear on the finishing reamer.
I have never used one and kind of doubt that anyone is doing that many Krag barrels to need one. So my guess is someone pulled the reamer out to clear chips and forgot to put it back in to finish. If the barrel had not been reamed at all , the bullet much less the neck would not enter the rifling.

Hopefully you can find a used one or rent one cheap. The offer stands for using the extension. One other option is finding a Krag smith that has a reamer. Should be a minimal effort and charge to finish it, perhaps less than a rental or a used reamer.

[IgnoramusRex]

Reporting back.

Got a field gauge. Bolt didn't close with fingertip pressure. Maybe only half-way rotated down into battery. Unless I'm an idiot, I'd say that this rifle is not too long in the headspace.

I'll be happily fire forming brass for it.

Thanks all for the advice.