Headspace Question

[archmaker]

Ok first time doing the Savage Barrel swap.

I have a go gauge and set my chamber up to just barely close on the go guage before tightening the barrel nut. Removed the extractor.

Went and shot 50 rounds, and I happen to have an old Remington barrel in the same chamber (243).

The go gauge sticks out of the Remington by .000" my fired brass by about .025". Which would indicate execessive headspace.

I also took a 40S&W case checked the inside diameter and it is .401, and measured the case length using it. I get (subtracting for the 40S&W case) 1.649 for the fired brass and the go guage is 1.626 (Forrester Go Guage, just checked should be 1.630), again a difference of .023". Using a paperclip I can't feel any seperation inside the case.

I then went to recheck my headspace with a piece of tape on the barrel. If I turn it a 1/2 of a turn (20TPI = .050" per full turn) then that should put me where my brass/remington barrel is telling me. But the Go Guage is now a no-go. Have to keep unscrewing the barrel until I can get the bolt to close, which puts me right back where I started. (I put a piece of tape on all the moving parts before i started).

Gun shot well and was accurate, but what I want to know is do I have a headspace problem and should I not use the go guage to set the barrel headspace, or better yet, what am I missing?

[archmaker]

I think I figured it out, yes it is .023 headspace issue, but the bolt/barrel is what is stopping the barrel from going any further, not the guage. I put the barrel on all the way it would go, then kept putting spacers under the Go guage until it would not work, it was at .024" when that happened.

I just took the barrel all the way off and checked, the go gauge is sticking out, but it is not sticking out far enough to slide the extractor under it.

So now to the next question, if I adjust my dies to the barrel will this work (only set the shoulder back a .001"), or should I return it. (Bought from Midway, Shilen 243 SS Barrel)

[GabbyM]

At this point you don't know if it's the barrel or the rifle that's off spec.

I would not even consider shooting it with .024" excess head space. You'll have ruined brass as it will be thinned above the web.
Find some blueprints and measure the receiver and barrel.

[archmaker]

So doing some more research on this, here is what I have come to the conclusion.

1. When testing headspace, know how much gap there is between the bolt head and the back of the barrel.
2. TRUST what the guage is telling you, I used a no-go Guage, but it would chamber. This is telling you there is a problem with #1.

I am going to fix the problem and actually headspace the barrel off full resized case using the shellholder and dies I will dedicate to this gun. What I think happened on shooting is that I had the bullets seated out to touch the rifling, so the case was all the way back in the chamber, then when I shoot the case expanded and blew the shoulders out into the chamber. If I had not set the bullets out to touch the rifling, it may have been a different results.

[GabbyM]

So you haven't measured anything yet and are fixing to set up the rifle with excess head space then blow out the brass to fit?? Is that correct? You do not want to go that route.

First off. How do you know the bolt is hitting the barrel before the barrel head spaces? Does the bolt lock up tight against the barrel and not move?

I'm thinking you need some help with this project that is beyond what forum advise is capable of providing.

If the barrel hits the bolt and headspace is still to long. Then the barrel is chambered to deep. Manufacturer will fix that. However I would be surprised if that's the case.

[archmaker]

Gabby, the bolt was hitting the back of the barrel, how I know this is, I would screw in the barrel until it stopped (no round in the chamber), open the bolt and turn it in a 1/16th of a turn and the bolt would not close. Measuring the amount of guage sticking out of the barrel indicates that the chamber is long, as there is only .098 sticking out, and according to SAAMI standards there should be .200 sticking out if using a go guage.

Shilen site states that the do go deep expecting a gunsmith to resolve the problem, by about .015", but that is on their standard barrels not the Savage drop in, I wonder if I received one that was bored too deep by accident.

Not going to shoot the gun with that too long of a chamber, will get it fixed so that my FL sized brass will close with about .001 clearance, and the bolt head will have about .005 gap (Savage standard is .010).

This has been a LEARNING experience, which I have enjoyed, figuring out what was going on.

[GabbyM]

Yes that sounds like the barrel is deep chambered. Probably happens but I'll bet it's rare out of Shillen.
Sounds like to contact Shillen to see what they want to do. They may have you take it to a gunsmith they use. Simple fix to set it up in a lathe.

Good luck

[fireball168]

Generally, the bolt nose to bolt face dimension on a Savage is right at .115". Measure yours.

The GO gauge you have should protrude from the breech face when inserted into the chamber .120"+. Most commercial barrels seem to be .125-.130". Measure yours.

That will tell you everything you need to know.

If the protrusion needs adjusted, let me know it is a relatively quick and inexpensive job to set the breech back a bit. Although I'm sure Shilen will take care of you.