45 ACP No-Go gauge length

[HumptyDumpty]

SAAMI specifies a maximum chamber length of .920". Would this be the length of a No-Go gauge as well? I'm attempting to craft my own by first cutting, then carefully hand-filling a 45 Win mag case.

[samari46]

Do the plunk test. I'm assuming it's a 45acp semi auto?. Take the barrel out and just run a couple patches down the tube. Plunk the sample round down into the chamber. If the base of the case comes out even with the hood of the barrel your ok. I've shot over 20K 45 acp and all of it in 1911 style pistols. Just plain jane hard cast 230 grain round nosed bullets. Frank

[HumptyDumpty]

Actually, I am installing a 45 ACP barrel on a Turkish Mauser action. I probably don't need to be all that precise, but I'd like to anyway.

[Jedman]

Well in the case of a bolt action you are the one that will determine what the max headspace will be.
I would set it up for .920 or a little less as I never seen ACP brass grow that long.

Jedman

[yovinny]

Back when I built my 45acp mauser, I just checked and set length with a sized case and a piece of shim stock to equal max cartridge length.
With the low pressure and that big mauser extractor holding it to the bolt face, I dont imagine you could get in much trouble with the chamber somewhat long.

[243winxb]

Notes
No-Go Gauge

Duplicates the distance over the maximum allowable, from the case head (or boltface) to the datum line(case mouth for 45acp) of the cartridge's shoulder, allowed within the chamber to secure a loaded cartridge and allow the breech to be closed in a safe manner for firing.
If the firearm locks up in battery when the gauge is inserted, then it is not within acceptable maximum headspace dimensions. The firearm should not be used and should be examined further by a knowledgeable gunsmith

[Greg S]

Cut some 308 cases on a case trimmer to .920 after a hack saw cut to rrmove the majority of the extra case length. Optimal length iis in the .902-904 area without looking at my class notes.

[Martin Luber]

I would think that excess headspace in a straight wall case has no impact with perhaps the occasional misfire or in a 1911, possible broken extractor as it is that which holds the case back against the breech and firing pin. Too little is a bigger issue as it won't chamber.
Thoughts?

[HumptyDumpty]

I'll be be using this for everything from standard 45 Auto, to top-end 45 Super loads. The barrel I've purchased uses a locking ring, so I can readjust without to much difficulty, should that be necessary. I've also never seen a 45 ACP casing over .920", and very few that actually were at the minimum of .898". It sounds like just a hair over .900" will be perfect.

[James Wisner]

Hope this helps, taken from my set of Clymer gauges.

OD at front .373"

Go overall length .898"

No Go Overall length .920"

When I ream chambers like this caliber with this much variation in length I try to go to the mid point between the two gauges.

JW

[HumptyDumpty]

Hope this helps, taken from my set of Clymer gauges.

OD at front .373"

Go overall length .898"

No Go Overall length .920"

When I ream chambers like this caliber with this much variation in length I try to go to the mid point between the two gauges.

JW
That helps immensely, thank you very much.

[Greg S]

As mentioned above, the majority of commercial/mil brass is in the .890 area. Starline is consistantly the longest factory that I have seen.