Headspace question

[relabbe]

I just put a new 300 win mag barrel on my 700 remington long action. I have a gunsmith book that states that the go gauge will fit if there is .220 inches. I used a new bullet and a shim on it back to measure my head space and I have about .218 inch of headspace. I cycled the rest of the my bullets in my gun and they all cycle nicely. Do I still need that .002 inch missing? If I need them I guess I should be lapping the lugs on my bolt.

What do you think? any advice...

Thanks,

[J E Custom]

My recomendation would be to buy a GO headspace gauge for
that round and use the shims on the back of the go gauge to
find the exact head space.

They are very cheep (Normaly $30 to $40 dollars.Brownells
sells Manson or Clymer.Mansons are a little cheeper and are just
as good.

I like .000 to.001'' but .002 to .003 will work.

Factory Loaded ammo is sized on the small side to work in all weapons
and if you use factory ammo to head space it will be smaller than SAAMI
spec.

And if you are .001 or .002'' less than you want then lapping the bolt is a good
way to increase headspace.

Better safe than sorry
J E CUSTOM

[specweldtom]

I have had a couple of rifles that would not take a go gage, but would chamber new factory ammo and unfired cases. I left them that way without any problems. On the belted cases, you might need a little more room if you switch ammo or use reloads fired in another rifle. Headspacing on the belt makes them unforgiving if the chamber is even a tiny bit short. I like tight chambers for accuracy and case life, but you have to be sure that the ammo you use will chamber cleanly.

I recommend getting your 'smith to try his go gage again, and if the bolt will close, then add shims until it won't. Then you will know exactly where you are. Presuming that the rifle is not a benchrest gun, if the bolt won't close on the go gage, I would touch the chamber with the reamer until the bolt will just barely close.

This is just my opinion and preference.

Good shooting, Tom

[relabbe]

Thanks J E Custom, I measured all my Factory Loaded bullets and the space between the ream and the head were all in between 0.215 to 0.218 inch. (winchester Supreme Nickel plated) which leaves a minimum headspace of.002 inch if your chamber is tight to the go gauge. The minimum headspace for the go gauge to fit is 0.220 inch and the no go gauge minimum headspace is 0.223. This means if you are using factory ammo and you are within the specification of the go gauge you can have up to .008 inch (0.223-0.215).

If all the factory ammo were perfect (all the same length), what would be the optimum headspace?

[relabbe]

Thanks Specweldton, I guess I should try the go gauge.

[J E Custom]

Relabbe

One more comment on head space.

.008 is the field gauge max (If it will close on this gauge then it is
rejected and considered not usable).

If you want good brass life you need to be under ,003 head space.

The reason for more .004'' is for better feeding in gas guns (M14,M16 etc)
with no intent of reloading the brass.

From an accurace standpoint "less is better". on the big weatherbys with lots
of freebore .000" headspace works the best for me, But it requires careful
sizing and reloading.

J E CUSTOM

[Kevin Cram]

You definately should use a go gauge. Remove the fire control and the ejector for a better feel too. If the bolt closes easily on the go gauge take a piece of clear scotch tape and attach it to the base of the go gauge. Trim the excess tape off with a razor blade. The tape is approximately .003" thick. The bolt should close nicely with just the go gauge and not at all with the scotch tape on. Don't rely on testing headspace using a piece of brass.