6.5 CM can’t get any velocity, opinions please

[AccelR8]

Sent you a PM with a link to a tool which can be use to cut a new throat.

 

[Gtscotty]

Based on your pictures, if I'm interpreting them correctly, you've got virtually no free bore. It looks like your rifling begins just about at the chamber...?

Yeah, that's a bit hosed up.... mystery solved I suppose.

 

[Gtscotty]

I would normally see about a 25 fps change per 1" of barrel length. Have been running my creedmoor at 30" length and averaging around 2875fps with 40.6 h4350 and 142gr. Can pump that up to 2975 fps with no bolt lift however the groups were not changing from 2875fps, also a light ejector mark on back of case. It does surprise me a bit the 20" barrel will hold velocities that fast but numbers dont lie. Any sign of pressure on your cases? What is your barrel life? How do you think the rl-16 compares to h4350, ur packing more grains in a case than me. Keep up the good work.

Yep, about 25fps per inch is a good approximation for the creed, at least in the 20"-26" range. Book loads with the RL16/RL17 top out a little over 2,800 fps with a 24" barrel and the various 140gr bullets, so ~2,700 fps is strong, but not crazy for a 20" tube. The factory 22" barrel gave ~2,760 fps with its preferred load of 42.5gr of RL16 under 140gr Accubonds. I don't know if the 25 fps per inch holds out to 30", I wouldn't be terribly surprised if there were some diminishing returns out past the more standard lengths.

To answer your questions, no marks on the cases, but then again these loads aren't above book max (not that that's a guarantee). Even when I had heavier bolt lift on the abandoned 43.5gr load, the cases looked ok, might have been a product of the Kimber bolt face geometry though.

I definitely do get better velocity out of RL16 than H4350 when using book loads. I used to run 42.5gr of H4350 under 140gr Nosler CCs for iirc ~2,750 fps in my RPR (24"). After ~1.5k I switched over to 42gr RL16 under 140gr RDFs at about the same velocity. The difference being, of course, the H4350 load was a grain or two over book max, and the RL16 load was a bit under book max (I tried faster, but that's where I found accuracy).

RL17 is supposedly faster, but can be temp sensitive. RL26 can give crazy velocities, but it stays sold out and doesn't exactly seem to give apparent pressure signs like most other powders.

 

[wagonman]

Roughly 3-6” in

your smith that wanted 80 bucks to scope his crappy work send him your pictures tell him that .199 freebore is not,there tell him to make it right on his dime, you have zero freebore not even compatible with factory ammo.

 

[ta6ppc]

your smith that wanted 80 bucks to scope his crappy work send him your pictures tell him that .199 freebore is not,there tell him to make it right on his dime, you have zero freebore not even compatible with factory ammo.

I’m really debating it, however I don’t want a worse or botched up job..

 

[acloco]

I’m really debating it, however I don’t want a worse or botched up job..

Find another smith. Unfortunate, but true.

 

[ta6ppc]

Find another smith. Unfortunate, but true.

The guy had a real attitude about me even asking, and the borescope comment was a huge flag.

im gonna move on to someone who I think I can trust and count on the quality of work.

 

[Breakshunter]

Get a new smith. Any smith with that attitude isn’t going to do any better the second time. Might take longer but having a gun that shoots awesome is way better than $500 tomato stakes! Ask me how I know! Lol!