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Gunsmithing Land to land dimensions?...

PlinkIt

GunNut ¯\_(ツ)_/¯
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Mar 30, 2014
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Virginia / North Carolina
Any insight where to find land to land barrel dimensions of various calibers?

Going to order a few pieces of ground rod from McMaster Carr and not sure where to find a good reference for land to land measurements

Found these numbers on another website for a starting point

0.2120 22LR 8893K191
0.2188 5.56mm 8893K193
0.2969 308REM / 300BLK 8893K219
0.3020 7.62x39 8893K221
0.3320 9mm 8893K228

But wanted to find some numbers also for:
6 / 243
6.5 / 264
6.8 / 270
7 / 284

Thanks for any insight

https://www.mcmaster.com/#catalog/124/3824/=1c8bcbx
 
If it is bore diameter you are wanting to know, those are listed on the Bartlien or Krieger website. Krieger has a more complete list.
 
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Just buy precision range rods from PTG. Lots easier

The PTG rods look to be 6 inches long, and likely great for centering up barrels for lathe work... But I'm not sure how I'd check clearance on a 9 inch suppressor with them... Unless I'm not seeing the right ones?... The ground tool rods from McMaster are 3 feet long

Not to mention 8 PTG rods would cost about five times as much as the 8 rods from mcmaster
 
Range rods have a long taper(3.5”)and are geared for working on barrel blanks. There’s such a thing as an indicator rod, which is identical except for a 1” taper, which would put a bunch more rod outside the muzzle, but not 9” out.


I wonder what the straightness tolerance is for the McMaster rods, as they don’t mention it. Also, they’re in the annealed state. I wonder how that would affect their long term usage?
 
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I spoke to Thunderbeast at shot two years ago. They were using gauge pins in combination with shim stock(to fit pin to bore) to dial in the muzzle prior to threading. I didn’t ask what they were using for checking work already completed.
 
Well, I’m kinda crude in lots of things I do. I am a Farmer. I bot my Buddy who does my smith work 22,6.5,30 cal range rods. When He go through threading my bbls, I pulled the bolts, made sure I saw daylight through end of suppressors and pressed the trigger. Ain’t messed a can up yet. Sometimes one can overanylize. Jus sayn
 
Well, I’m kinda crude in lots of things I do. I am a Farmer. I bot my Buddy who does my smith work 22,6.5,30 cal range rods. When He go through threading my bbls, I pulled the bolts, made sure I saw daylight through end of suppressors and pressed the trigger. Ain’t messed a can up yet. Sometimes one can overanylize. Jus sayn


You haven’t shot the can because your gunsmith is doing his job, and has nothing to do with your inspection method. Just sayin
 
http://www.jgstools.com/mainarea.html
Go to the standard pilot set link on the side bar. Standard land-land bore sizes are listed..
These numbers look very close to what I see on the barrel makers info thanks for the cross reference


Range rods have a long taper(3.5”)and are geared for working on barrel blanks. There’s such a thing as an indicator rod, which is identical except for a 1” taper, which would put a bunch more rod outside the muzzle, but not 9” out.


I wonder what the straightness tolerance is for the McMaster rods, as they don’t mention it. Also, they’re in the annealed state. I wonder how that would affect their long term usage?
Good questions, and I am going to take the chance considering the rods are all 1/5 the price of the actual alignment rods. I will Report as soon as I see how they work


Well, I’m kinda crude in lots of things I do. I am a Farmer. I bot my Buddy who does my smith work 22,6.5,30 cal range rods. When He go through threading my bbls, I pulled the bolts, made sure I saw daylight through end of suppressors and pressed the trigger. Ain’t messed a can up yet. Sometimes one can overanylize. Jus sayn
If I can buy a 5 dollar rod that will let me see if I a going to wreck a can I will spend that happily, good luck with your cans. I am attaching to factory rifles in several scenarios as well, I may not have gotten as proficient of a smith as your friend
 
I've bought/used the O1 drill rod from McMaster. You're going to want to cut to useable length, chamfer/square the ends and check for straightness (roll on glass surface/etc). Visual down the bore and a double check w/ rod should let you know if any alignment issues.
 
I've bought/used the O1 drill rod from McMaster. You're going to want to cut to useable length, chamfer/square the ends and check for straightness (roll on glass surface/etc). Visual down the bore and a double check w/ rod should let you know if any alignment issues.
I figured they were longer than I needed by a good bit, hoping if they have a bend it will be to one end so I can cut it off. Did the examples you received work well for this?


My Mk 1 eye ball, has never missed one to-date.
I don’t trust mine that much, I have several I’m afraid to try the can on because I can’t tell.


Agree, I did the rods more just because they were cheap and forced me to return the Geiselle rods I convinced myself I needed.
I take it there was no real benefit to the geisselle rod vs the drill rod? And I’m with you in the price vs the G rods. $55 bucks shipped for 8 of them, should be enough to do every caliber I have if they work
 
I take it there was no real benefit to the geisselle rod vs the drill rod?
Not that I could see. However I was able to cut/chamfer on a lathe and roll on a surface plate. Not sure how doing by hand would work out but should be fine if done carefully.
 
Any insight where to find land to land barrel dimensions of various calibers?

Going to order a few pieces of ground rod from McMaster Carr and not sure where to find a good reference for land to land measurements

Found these numbers on another website for a starting point

0.2120 22LR 8893K191
0.2188 5.56mm 8893K193
0.2969 308REM / 300BLK 8893K219
0.3020 7.62x39 8893K221
0.3320 9mm 8893K228

But wanted to find some numbers also for:
6 / 243
6.5 / 264
6.8 / 270
7 / 284

Thanks for any insight

https://www.mcmaster.com/#catalog/124/3824/=1c8bcbx

oh my. Go to www.saami.org, which will give you the standard bore diameters, or http://www.cip-bobp.org for the metricated.

22LR--.217
5.56--.219
308/300BLK--.300
7.62 x 39--.300
9mm parabellum--.346 sometimes .347
6/243--.237
6.5/264--.256
6.8/.270--.270
7/284--.277