garand muzzle gauge

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tankmech

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a while back i took my garand to a very compitent gunsmith to have my s.a. 48 barrel re-crowned cause the muzzle had obvious uneven wear at the end. i asked if he could re crown the muzzle but retain the factory contour of the muzzle and he explained that he didnt have the proper crowning tool but he could put the crown on the inside and he would drill down 1 tenth of an inch and that would correct every thing and i have to say he did an excellent job. some time passed and i decided to get a muzzle gauge looked online and got one from a person whos name im not gonna mention but hes supposed to be THE guru of the garands anyway,when i got the gauge i immediatly checked my newly crowned muzzle and it gauged a 3 i thought this cant be right so i emailed him and he responded that his gauges are accurate and has a return policy if i choose to go that route i took him for his word and kept the gauge and then decided to do some more in depth measuring this is what i found... the gauge is encrimented in 1/8ths not 1/10ths i used a fine tipped marker to make a mark on the gauge subtracted 1/10th to compensate for the re crown and the new mark was just above the "2" on the gauge i then used my caliper gauge and got a reading of 3015 or 1.5 im happy and frustrated at the same time cause i thought the barrel was still a paper weight but now i know its still a good shooter. sooner or later ill get a more accurate gauge but if anyone has doubts about their muzzle gauge pull out that marker and caliper and GAUGE the muzzle gauge to see if its accurate
 
Out of curiosity, how did it shoot before you had it recrowned?

Your post is hard to read, BTW. If you broke it up some it would be easier.

FWIW, I would trust a Duff gauge.
 
i plan on doing that but im also gonna get some gauge pins made instead of the traditional tapered type im gonna get individual ones made 3 or 4 of them.. 300,301,302 and 303 and maybe 304 i think that would give me a more accurate assesment
 
to tim the student, sorry about RUN-ON rant at 75 yrds the grouping would fit inside of a 6 inch circle now it shoots inside of a 3 inch circle but not real tight could be stock fit and more then likely its also my trigger squeeze BTW i was using a duff gauge. and with a tighter grouping after the crown job i couldnt wrap my head around a muzzle that still gauged a 3 so i began questioning the accuracy of the gauge. IM IN NO WAY!!! trying to bad-mouth or drag MR. DUFFS name thru the mud as with any machined tool or part theres gonna be at some point, items with broader tolerences than what was intended im sure theres hundreds maybe thousands made at a time and some part of the process got out of whack and i may have gotten one of those
 
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Having the barrel "counter bored" well still leave you with the same barrel wear reading. Your groups improved because of the new crown.

3" groups from a field grade Garand is good in my book.
 
What ammo are you using to check your group size? Have you checked to see if any wood is touching the op rod or binding some place. Is the reciever tight in the stock? Maybe the rifle will shoot tighter with reloads.
 
im using surplus greek ammo the reciever fits tight and the op rod isnt binding or touching the wood
 
OK, subtracting the 1/10 rebate, you are close using the gauge. No matter if it gauges 1.5 or 3 - as long as it shoots well, it's fine. I would not use Greek as the test ammo. It's fine battle ammo, but a rifle test is not a fire fight. I'd be using match ammo to tell how well any barrel shoots off the bags.
 
what all needs to be considered when using match ammo such as...... maximum grain bullet...gas plug etc,etc.
 
There has been plenty of M2 equal Match ammo manufactured. It's a fairly steady seller for MFGs. As long as it's M2 equal, it's Garand ready :)
 
You do realize that USGI NOS never used Garand barrels dont always measure 0,in fact I have owned several and a few measured up to 1.5 on the muzzle.
 
I cannot comment on the Duff gage but I can on the CMP Gage. I have one and as others say a new barrel can measure several variations and I have new barrels that will read 2.

As well if the barrel is a after market barrel you may get all kinds of variations as there is no criteria for a civilian contractor to have a barrel measure 0 or anything for that matter. It passed inspection if your check cleared his bank.

You cannot bet all or make comments at all based on the gage reading as you really don't know what the barrel measured when new and unfired. In other words you don't really know where you are when you drop a gage into a barrel unless you know what it was in unfired condtion.

Thusly to correctly use a muzzle gage since there was never a gov't standard for such can well be a exercise in futility. The dimensions of the gage was made up by Bruce Woodford who had access to hundreds of 30 cal match barrels as he was the intructor in the National Match School at RIA and worked the RIA/DCM van at Perry for years and as well a long time friend. There was never a gov't study to confirm the data based on a controlled test as there was on the gov't M1 and M14 and M16 and 1903 gages.

I have a number of 30 cal rifles and I have gaged them and found various readings and I have exact numbers of rounds on all my rifles.

For instance I also have M1 and M14 throat gages and I have rifles with all kinds of round histories on them and there is all kinds of gage readings that don't necessarily correlate with the gage. For instance I once barreled up two 30.06 rifles from the same company that came in the same shipment. I headspaced both rifles to snug on a GO Gage. Theoretically if the barrels were identical and chambered with same chamber reamer the readings would be the same. There was 1 1/2 rings difference in the two barrels. Why? Simple when you buy barrels from a vendor as an individual you have to take what he gives you as HIS STANDARD. The gov't buys to a spec and they are inspected by an inspector to insure conformance.

So now my procedure is as follows on new barrels. After chambering I will fire five break in rounds cleaning/copper removal between each round and check the throat for the initial reading and the muzzle and record them in a round history book I keep with each rifle. At 100 rounds I generally gage again, then 500, 1000, 1500 etc. That way I know where I started and what has happened and the exact number of rounds that have gone down range and the loads.

As someone mentioned above the Greek ammo is not necessarily the best stuff to determine accuracy or lack thereof as the acceptance dispersion for Greek Ball ammo is unknown. I can absolutely say with certainty there is a US Gov't standard for ammo and I am aware of variances in match ammo that was accepted that exceeded the specification.

A good all around 30-06 accuracy load I use is 43.3 Gr. 4895 with a 168 Sierra MK bullet, Wolf primer. The load for the 30.06 Match round was 47 gr. 4895 with 173 gr bullet in all the lots I have pulled bullets and weighed charges from.

Also be advised the 173 bullet will measure .308 to .3089 and still be in spec with most of them I have measured .3082-4".

Acceptance accuracy on the Garand was 5" at 100 yards and rejection was 7.5". Neither of which is acceptable to any match shooter I know that is any good. A good M1 will shoot close on to 1" at 100 yards but you are not likely to find one from the CMP racks.

43.3 gr. 4895 may or may not work your Garand but it works absolutely fine in a Mod 70 bolt rifle and a 1903A3 Springfield with a new barrel and will give you a good indication of how good your barrel is.
 
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A good all around 30-06 accuracy load I use is 43.3 Gr. 4895 with a 168 Sierra MK bullet, Wolf primer.

Sounds like a good 200 yard match load, Hummer. Very similar to my 37.2gr 4895, 168SMK, Russian primer .308 Win load that I use for 200 yard F Class Matches. Perhaps 2300fps, which was pretty much what the International 300 meter Match loads were.

Don
 
a new barrel can measure several variations and I have new barrels that will read 2.
OP, I'd worry less about the gauges and shoot it more (No offense intended). What the folks above have stated is true. New muzzles can be a whole lot more than what yours is now. The Greek ammo you're shooting is good ammo, but not match ammo. Also, the TE measurement has a higher affect on your accuracy, so it could be argued you're looking at the wrong end of your rifle with those measurements!
 
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