Maybe. But there is no guarantee that changing the bolt would cure excessive headspace.
I've heard of it being done, but have no personal experience. Boltface could also be cut back and a disc silver soldered on.
5440's badly pitted one would be a good candidate for an experiment.
tiriaq: I've never seen a bolt head pitted like that before, is it headspacing alone that would cause this to happen?
5440fight: Just keep in mind that if you rifle is a original and matching you may want to try to keep the original bolt and work with that. Although a mismatched working rifle is better than the alternative. It sounds like you own other Enfields, so if I was you I'd gradually acquire more spare parts, they are great to have especially if your planning on buying more rifles in the future. I've had to fix the headspacing on several rifles over the years and having a handful of bolt heads is great. Really they aren't that expensive and they will save many headaches over time.
I also have a question regarding that bolt head, was it always pitted since you owned the rifle, or has it developed while you've owned it? If the latter, how long did it take to get to that point?
I recently purchaced a no1 mk 3 with the same problems. The rifle came with two bolts, the original and a spare. I Picked up a third bolt with a longer bolt head, so now I could play with the other bolts. The one I did solder a disc to the face, put a spent case in my chamber and kept facing the bolt head on the lathe til I could just close the bolt. The other, I put a small weld on each side of the bolt and ground them until it fit snug on the spent casing, then off to the range. Both solutions worked.
commercial ammunition seems all to be loaded to upper limits as far as oressure is concerned. you will have a lot less problems if you handload, keeping your MV down to about 2250, which gives the best accuracy, anyway.
also, as has been pointed out, fireforming for your chamber can help a lot.
much commercial brass has rims that are too thin, and this is where the cartridge headspaces when you are using a rimmed cartridge. i have measured commercial cases as thin as .037" rim thickness. military standard was as close to .064" as possible. the most consistent boxer-primed brass for the .303 that I have ever found is the WW2 stuff made by Defence Industries (DI Z 194X headstamp); it all is so close to military max, and therefore minimum headspace, that it's almost scary. just wonderful stuff, getting a little long in the tooth by this time, but you can do a lot with a propane torch and a sinkful of water...... it also fireforms nicely. how long it lasts, i have no idea. i fireformed a box for my Ross and it has done 14 firings, still doesn't need trimming....... but that's with mild (darned accurate) loadings.
good luck with the project.
All the metal on the rifle was great, no rust or pitting. Even had all the anti-rust paint from the forties under the wood. Only the bolt head looked like that, even the rest of the bolt looks great. I assume that bolt head has been shooting corrosive stuff since 1917, and someone was not a carefull cleaner. It's not from this rifle, I shudder to think what the rest of the gun looked like.



























