Headspacing?

p.Rundle

p.Rundle

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So I've been working waaaaay too much to go out shooting but my birthday is coming up...lucky me! So I'm going shooting to celebrate and I hope to blast with my P14 Enfield that I just traded for. Should I headspace it first, and how do I go about doing that? I know about go-no-go gauges and stuff, but I don't really want to buy one and wait for it in the mail. Do I take the risk and just shoot 'er? I live in Calgary, and I'd be willing to pay a few bucks to borrow a no go gauge for the .303 in case anyone is willing to help me out.
 
Does it have a matching # bolt and appear to be in generally good condition? If not, it might be worth the effort to check headspace. The P14 action is heavily over-engineered for .303 but nothing special in how it handles escaping gas. You could also set it up in a stand or with sandbags and fire a couple of rounds with a string and have a hard look at the brass. People worry a lot about headspace but, with Lee Enfields, I've only found one with failing headspace (out of a couple of dozen or so that I've checked) and it was a very, very tired rifle. If you do get gauges for your P-14 be aware that the camming action upon closing the bolt is very strong and you want to use next to no force on the bolt handle to detect resistance.

milsurpo
 
Headspace is only a real issue if it's in the large side and you continually full length size the same piece of brass over and over after firing. If you neck size after initial firing there is no headspace issue, it's corrected by the fire formed brass.
Similarly, if you are only shooting factory ammo there is very little to worry about as it can take a pretty good stretching for a single firing.
Here is a 7.62x51 case that was fired in a 30'06. Headspace in that instance would have been almost 475thou over vs 4 or 5 thou the gauges measure.
 
Headspace is something that is nice to know, but you are not going to get a catastrophic failure from simple excess headspace. As mentioned above, the worst that is likely to happen is a case separation: annoying if the front part gets stuck in the chamber, but no disaster. An extreme example is .308 fired out of a .30-06 chamber. The usual result is a straight-walled case with almost no shoulder left.

Look at the once-fired cases for signs of incipient head separation. A bright narrow ring on the outside is the obvious one. There may also be thinning on the inside that you can feel with a dental pick or a hook made from a paperclip, even if you can't see anything on the outside.

Excess headspace on something like any of the recoil-operated Browning machine guns certainly can cause catastrophic failure, but this is because the case is unsupported if the barrel is not screwed far enough into the barrel extension.
 
headspacing :) I have a few 30-30 cases that were fired out of a 303. 2 of 3 split.

the Patt'n 14 is a strong action to start with, so unless you see obvious signs of damage I would just shoot it and then look at the fired case.
 
pRundle: A bit of trivia re the P14- interchangeability between rifles from the three manufacturers was, presumably, not great. The British listed bolts as one of the not-interchangeable items. When manufacture was switched over to the 30-06 Model of 1917 this issue was largely overcome. Is your bolt the same manufacturer as the barreled action?

milsurpo
 
burnt_servo said:
308 fired in a 30-06 is a poor example.

it is my understanding that 308 was designed to be safely fired in a 30-06 chamber
Click to expand...

7x57 in a 270?

I think a lot of whether it will fire or safely fire depends on the action type and ejector type. CRF will keep the case head on the bolt so there is little head expansion even if it's a 7x57 fired in a 270/280/30'06 etc. Just the shoulder and neck blow out to fill the chamber.
 
you can add .308 in 7.5x55 swiss (k31) to that list, I was there when Diopter tested it (and we were getting surprisingly ok velocities on the chrono!)
 
Hitzy said:
7x57 in a 270?

I think a lot of whether it will fire or safely fire depends on the action type and ejector type. CRF will keep the case head on the bolt so there is little head expansion even if it's a 7x57 fired in a 270/280/30'06 etc. Just the shoulder and neck blow out to fill the chamber.
Click to expand...

I think you missed what I was getting at ..........

the case taper of the 30-06 and the diameter of the shoulder of the 308 are designed in such a way that if a 308 is accidently dropped into a 30-06 chamber , the shoulder of the 308 is supposed to headspace on the gradual taper on the 30-06 chamber .
I believe it was 45acpking that I first heard this from .
 
I'm in Calgary and have a 303 field gauge. You're welcome to come over and shoot the breeze and see if it closes or not, if it makes you sleep better at night haha. Not really an issue with a rimmed cartridge though.
 
burnt_servo said:
308 fired in a 30-06 is a poor example.

it is my understanding that 308 was designed to be safely fired in a 30-06 chamber
Click to expand...

burnt_servo said:
I think you missed what I was getting at ..........

the case taper of the 30-06 and the diameter of the shoulder of the 308 are designed in such a way that if a 308 is accidently dropped into a 30-06 chamber , the shoulder of the 308 is supposed to headspace on the gradual taper on the 30-06 chamber .
I believe it was 45acpking that I first heard this from .
Click to expand...

It's not the shoulder but the body of the 7.62x51 that is a hair larger then the body taper on the 30'06. And yes, whether it was intentional or accidental is not really clear, but it's enough that you can't just run a reamer through a .308 to make it a 30'06.
 
burnt_servo said:
I think you missed what I was getting at ..........

the case taper of the 30-06 and the diameter of the shoulder of the 308 are designed in such a way that if a 308 is accidently dropped into a 30-06 chamber , the shoulder of the 308 is supposed to headspace on the gradual taper on the 30-06 chamber .
I believe it was 45acpking that I first heard this from .
Click to expand...

Technically you should not be able to close the bolt on a 308 case in a 30-06 chamber.

Reality is often different from theory however.
 
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