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View Full Version : Do I have to set headspace after replacing my bolt?



Eckstream1
07-26-2018, 10:17 PM
Long story short:
I purchased a used 110BA LE in 300 Win Mag and the incorrect bolt was included.
Savage sent out the correct bolt for the rifle but my local shop doesn't have headspace guages for 300 Win Mag.
I removed the firing pin, ejector and extractor and chambered a factory Hornady round. Everything seems good...

Should I buy a set of go/no-go guages before i head to the range?

RustyShackle
07-26-2018, 10:42 PM
Yes! I can’t believe they up and sent you a bolt!??? (Assuming it was the whole getup with new bolt head)

Eckstream1
07-26-2018, 11:11 PM
I figured as much...
They sent the complete bolt (forgot to install the ejector, spring and retaining pin) to my local shop.
They just don't have the guages... So I ordered them and a barrel wrench.

bsekf
07-27-2018, 08:01 AM
YES However, stick a couple of pieces of scotch tape on the case that chambers, if bolt won't close or closes hard, you should be good to go. If you reload, headspace it relative. You just don't want it so long you get case separation.

Bill

Balljoint
07-27-2018, 11:24 AM
In a WORD YES to CHECK HEAD SPACE

LHitchcox
07-27-2018, 12:26 PM
You may not have to reset headspace, but you must check it. Gauges are great, but Scotch tape will confirm the setting. As posted above, use the tape as a safety check. Start with one layer at a time and see how many layers before the bolt won't close.

Texas10
07-27-2018, 04:48 PM
I sent a new model 12FV 223 back to Savage twice to fix a chamber issue, and then a firing pin issue. Been shooting fine since, very accurate in fact. But I was barreling a 223 the other day and had my go gage set out, so what the heck, I put the NO GO gage in the gun Savage had fixed, and the bolt closed just fine. Added 1 layer of tape to it and it still closed with a bit of effort. Since I hand load, and don't full length size the brass, its fine. And it shoots factory ammo without problems.

J.Baker
07-27-2018, 11:01 PM
Go/No-Go gauges are subject to tolerances just the same as everything else. Buy three sets for the same cartridge from three different makers and and they'll all be slightly different but within 5-10 thou of each other.

PB_Crisp
07-28-2018, 12:56 PM
Within 5-10 thousandths?
Isn't that a huge amount for gauge variation?
I'd expect 0.001"
But I could maybe see 0.002" to account for folks not having the same expectations.

I like DIY. The barrel nut just makes sense. -PB

J.Baker
07-28-2018, 04:41 PM
One has to remember that all SAAMI specifications are 100% voluntary, meaning they aren't carved in stone and there's no penalty if something doesn't meet their established specs. As has been discussed here ad nauseum in the past, you won't find a factory barrel that has a chamber that's to SAAMI spec as every manufacturer has their reamers made to their desired specs (usually with longer throats/freebore). Headspace gauges often differ in length from manufacturer to manufacturer based on how they decide to spec them within the SAAMI specs.

For instance, Fred headspaced the .284 Win barrel on my Axis with his Go gauge after T&T'ing the action (not sure of the gauge brand - but I'd guess PT&G or Dave Manson). I happen to have a set of JGS .284 Win gauges from a past project series we did here on the site, and when I try to close the bolt on my JGS go gauge it won't close indicating the headspace is too tight. Like I said before....tolerances. The gun shoots fine and my FL sized brass chambers fine so I see no need to mess with it.

The below is an excerpt from a document put out by Dave Manson Precision Reamers (link (https://mansonreamers.files.wordpress.com/2015/06/headspace-gauge-dimensions-and-tolerances.pdf)):



Confusion often arises when comparing headspace readings generated by gauges from different manufacturers--a rifle may accept both “GO” and “NO GO” gauges from one maker but only the “GO” from another. This would lead a reasonable person to ask, “why?” The answer lies in the dimensions and tolerances to which the gauges are made.

It’s important to understand that the various makers of headspace gauges do not use the same dimensions for what is termed “GO”, “NO GO” and “Field”. We know the specifications used in the manufacture of our gauges, but cannot speak to those used by other makers--except in very general terms—so the information given here applies only to Manson-manufactured head space gauges.

We use both a two-gauge and three-gauge system for checking headspace. Three gauges (“GO”, “NO GO”, and “Field”) are used with rimless, shouldered rifle calibers, eg. 30-06. This is done because SAAMI allows .010” between minimum and maximum headspace for these chamberings. Many feel (ourselves included) that only knowing headspace within .010” is imprecise and that an intermediate gauge is called for.

In rimless, shouldered calibers, our “GO” gauge corresponds to the SAAMI (or industry) minimum; “NO GO” is ground to minimum plus .006”; “Field” corresponds to SAAMI maximum (min. plus .010”). Our manufacturing tolerances are such that actual gauge measurement will always fall within SAAMI limits.

We offer two gauges as standard on all other calibers—shotguns, rimfire, rimmed, belted or rimless pistol(45 ACP). In this system, “GO” corresponds to the SAAMI (or industry) minimum and “NO GO” to SAAM I maximum. Again, tolerances are such that actual gauge measurement will fall within SAAMI limits.

We do make headspace gauges on special order to specifications other than those outlined above. All such gauges are clearly marked and are easily differentiated from our standard product.

Eckstream1
07-30-2018, 05:28 PM
Thanks guys... Found a smith in my area with a set.
Everything was good to go... Finally got to shoot my new rifle!