6mm ARC Velocities

Purchased some of the 107 TMK to try in both my 16" and 22" barreled rifles. Based on load data I expect to see speeds of 2600 to 2800 depending on barrel length using either Lever or CFE223. I'll be using Starline brass and pushing for bolt action pressure.

Jay
 
Joining the 6 ARC club.

I just received an 18” Shaw 7.5 twist gas gun barrel in the mail. I’m waiting on parts to finish the upper. I also have 1K 95 TMKs on the way. I will be using CFE 223 which I have in ample supply.

I’m not sure which direction I want to go as far as brass. I’m not super interested spending a grip on Alpha brass for a gas gun. I can get Hornady brass in quantity for very cheap. Normally I hate Hornady brass, but perhaps it will work fine in the lower pressure application.

I’m not looking to push the limits in my gas gun like I would with any of my bolt rigs. That being said, I’m looking use published loads. I have a copy of the 11th edition of the Hornady book and can also reference Hodgdon’s site as well. Hornady’s lists 29.4 gr as max while Hodgdon lists 30.4 gr max.

Does anyone have experience on which max I listed above seems to be more accurate/true and an accompanying velocity?
 
Joining the 6 ARC club.

I just received an 18” Shaw 7.5 twist gas gun barrel in the mail. I’m waiting on parts to finish the upper. I also have 1K 95 TMKs on the way. I will be using CFE 223 which I have in ample supply.

I’m not sure which direction I want to go as far as brass. I’m not super interested spending a grip on Alpha brass for a gas gun. I can get Hornady brass in quantity for very cheap. Normally I hate Hornady brass, but perhaps it will work fine in the lower pressure application.

I’m not looking to push the limits in my gas gun like I would with any of my bolt rigs. That being said, I’m looking use published loads. I have a copy of the 11th edition of the Hornady book and can also reference Hodgdon’s site as well. Hornady’s lists 29.4 gr as max while Hodgdon lists 30.4 gr max.

Does anyone have experience on which max I listed above seems to be more accurate/true and an accompanying velocity?
Hornady or Starline brass would work just fine in a gas gun. No way would I want to use premium brass, too afraid of losing it:)

Figure out which load is max in your gun, might be 29.4 or it may be 30.4.
 
Hornady or Starline brass would work just fine in a gas gun. No way would I want to use premium brass, too afraid of losing it:)

Figure out which load is max in your gun, might be 29.4 or it may be 30.4.
Exactly! I don’t want it to eject in some bush somewhere!

From what I’ve found, Hornady tends to be light on their published loads. That’s for multiple cartridges I have loaded in the past.
 
Hornady or Starline brass would work just fine in a gas gun. No way would I want to use premium brass, too afraid of losing it:)

Figure out which load is max in your gun, might be 29.4 or it may be 30.4.

100% agree - I hate losing a piece of Alpha, Lapua, etc.... Stick with cheaper Hornady or Starline for a gasser. I still use a brass catcher so I'm not leaving brass all over the ranch.
 
I'm using Starline brass for my bolt action. Measured the brass at the neck with a ball micrometer and all of the pieces I've tested in multiple locations on the neck were .013-.0135. Not the thickest, but pretty consistent thickness. I'm getting SD of 8.1 over 20 rounds using 108 ELD-Ms, Staball Match and GM205M primers which also reflects well on the brass. Probably won't get as many firings out of it but so far, I've been happy with it.

Also just wanted to point out that in the 11th Edition of the Hornady Reloading guide, the COL for 109 ELD-Ms was listed at 2.540 and in the 12th the COL is listed as 2.245. That long COL in the 11th edition is the reason that I didn't go with 109's for my initial loading - I should have known better.
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