It's nothing fancy. I'll try to take some decent pics this weekends.
That's a pretty sleek looking rifle, nice work.
Yes it is the Harvestor 30. I love it.
I've been meaning to post this up, thanks for the reminder.
So that its available via the search function, in most cases:
SAAMI minimum is the length used for a go gauge.
SAAMI minimum plus .004 is the length used for a no-go gauge.
SAAMI maximum is the length used for a field gauge.
There are always exceptions, of course, and all are measured from the datum line (which is sometimes hard to find without the proper tools) and the cartridge base.
Originally Posted by keeki
Guess it doesn't really matter. If ya cant afford $15, you won't be buying much anyways
That is a simple explanation and in most cases right, but technically incorrect.
The difference from SAAMI minimum to maximum length is .010". The difference from a go gauge to no-go gauge is .005", with a tolerance of +-.001". The range of the go/no-go gauges have to fall within that .010" window of the min/max headspace length. This is called a geometric tolerance. So technically a go gauge could be as little as minimum length, to min. + .006". A no-go gauge could be as little as minimum +.004" to maximum length. Yeah, sounds confusing, but SAAMI specs are very wide, and most manufacturers use them as a "suggestion" then use what is called "voluntary industry specs" to keeps things in a more realistic realm.
Most of the general public believes that every manufacturer uses SAAMI specs in every aspect of chambers and ammo, and that is simply not the case.
"As long as there's lead in the air....there's still hope.."
Oh, one more thing.....SAAMI doesn't call out specs for a "field' gauge. That is a military spec, being ,.015" longer than a go gauge.
"As long as there's lead in the air....there's still hope.."
That's a bummer! I've had a bad PTG reamer and a bad Manson reamer. I don't have a lot of experience with reamers, but my PTG had a burr on the shoulder, so only one flute was cutting the shoulder. I caught it before I finished the chamber and finally figured out what was going on. I stoned down the burr and finished the chamber.
On the Manson (had it less than a month), I reamed a new barrel, but in my inexperience, I didn't realize that the pilot was too tight and I pushed the first 1" of the rifling out maybe 0.0005". The barrel is probably still okay, but I ordered a new one anyways. I noticed that the etching on the pilot was worn on the first .2" but not on the rest of the pilot. The pilot was about an inch long before any cutting flutes were present. I drug out a B&S micrometer and the first .2" of the pilot measured 0.30000" (a .308 M852 match reamer). The rest of the pilot was 0.2998".
I ended up chucking the reamer in a drill and used a very fine stone to bring the oversized part of the pilot to match the rest of the reamer.
I haven't had a lot of luck with reamers. I do have a 10-piece PTG headspace gauge set for 308 and it seems to work very well. I've verified headspace in SAI rifles and they seem to be accurate. Headspace on a new rifle was about 0.002" over SAAMI minimum headspace.
Tony.
I wonder if those gauges aren't for a 6.5 Sweed?
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