Winchester 1894 .38-55 headspace

[LonesomePigeon]

I was given a Winchester Model 1894 Sporting Rifle .38-55 that was made in 1894 or '95. It has been refinished. I know it's black powder only, I made a few bp rounds, shot about 9 of them and some of the primers backed out. I also checked it with the method where you insert a spent primer into a new brass and seat the primer with the action. The primers did not seat all the way, thus it appears to have a headspace issue.

I left a message with a local gunsmith that I have used before but he has not returned my call yet. Now I know you can buy an oversize lock bolt, my question is if I install an oversize lock bolt would that be likely to fix the headspace? Is this a drop in part or would fitting required?

 

[Scooter22]

How light were your loads? Backed out primers can happen with them. The FP kicks the case forward and it grips the chamber wall but the pressure doesn't seat the head of the case back against the bolt face when fired so the primer backs out. Nice rifle!

 

[LonesomePigeon]

I don't remember the exact grains but it was a full case of Goex 2F lightly compressed. Bullet was pure lead cast from an old Ideal tool labeled 38-55M, which I understand was originally for a Marlin. Starline long brass. My grandpa also had some old factory Remington and Winchester brass with the rifle and they also had backed out primers.

 

[czhen]

LonesomePigeon
Reloading is not an area of my expertise, but this is a beautiful rifle. Hope you find the right load for it.
Please post some target when you find it.

 

[Old Stumpy]

Homestead Parts sells locking bolts in increments of .005", .010", and .015" oversized for pre-1964 Winchester 94s.
Which one would depend upon the amount of excess head space that exists.
Whether it would fit into the locking bolt mortises and slide freely, who knows?
If not then fitting might be required on the sides of the portions that actually fit into the mortises.
The front face of these portions might need to be fitted to the mortise, but no metal should be removed from the rear faces.
Hopefully though it would drop in okay.
In order to figure out which locking bolt to order you would have to measure the amount of excess head space before ordering.
According to what I read you can use the primer method to measure it fairly closely.
Correct headspace should be a minimum of .063" and a a maximum of .070" SAAMI.
Since the case head spaces on the rim, and the rim is a maximum of .063" thick, that is set as the minimum headspace.
But it could be up to .010" less depending on the ammo maker. So .058" might be the average rim thickness.
Anyway, if your chamber is clean and no debris is in the rim area, then you would use a brand new unfired case and repeat your primer headspace test. It would be best if you remove the extractor.
Using accurate dial calipers, you would then measure:
1) The thickness of the rim. 2) The overall length of the case alone. and 3) The overall length of the case including the spent primer.
Subtract the rim thickness from the case alone length. Then subtract this amount from the case length including the spent primer.
This will be your actual headspace for your rifle. If it measures more than .070" then it is excessive.
So, you would then figure out which new locking bolt thickness would get you closest to .063" but not too close.
If your headspace is .075" then the .010" locking bolt would reduce it to .065" which is very good, but near minimum.
If your headspace is .081" then the .015" locking bolt would reduce it to .066" which is very good.
If your headspace is .084" then the .015" locking bolt would reduce it to .069" which is acceptable.
If your headspace is more than .085" then the .015" locking bolt won't correct your excess headspace problem.
Anyway, you get the idea.
I've never done this so I don't know how well it would work out. Your results may vary.

 

[Old Stumpy]

I own an exact twin to that Ideal loading tool, except in .45-70 Government for the 500 grain bullet,
Same flaking nickel plating. Same adjustable seating and crimping chamber.

 

[LonesomePigeon]

Thanks Old Stumpy, that explanation is quite clear.

I think it's a beautiful rifle too, I will certainly post some targets when I get it working.