Dickturpin
Well-Known Member
Guys I'm looking at buying a 6.5 creed moor...looked at a few and noticed some some with a 20" barrel as opposed to some with 24" barrel??? Anyone know the difference in velocity??
rifleshooter.com
Mines a 24” but for deer use there’s little lost with a 20”...
I’m just modest!Forgive me it I do not take advice on length, from a bloke called Stumpy...
I have a 20” barrel Tikka T3 in 6.5CM.
I shoot factory Hornady 140gr eldm. The box speed is given as 2710fps. My actual chronographed speed is 2570fps.
I hope that helps.
Unusually, standard MVs quoted for the 6.5 Creedmoor are from 26-inch SAAMI-standard barrels. (This barrel length is usually only quoted for very over-bore capacity magnums.) 140 fps MV loss for six inches of barrel sounds about right for this cartridge, especially as a factory barrel and chamber may not be quite as tight as a SAAMI-spec test barrel.
Don't see the point if you're intending to use factory ammunition, I would have thought their are better options, but if you reload, so you get the best from it, it doesn't look bad.
A quick play on Quickload, shows an estimated 2790fps is achievable, from the ELD-M 140gn, 20" barrel. Roughly 10% below max pressure.
What powder out of interest as that’s a lot from a 20” barrel! If RS60 / RL17 quick load definitely over estimates things.Don't see the point if you're intending to use factory ammunition, I would have thought their are better options, but if you reload, so you get the best from it, it doesn't look bad.
A quick play on Quickload, shows an estimated 2790fps is achievable, from the ELD-M 140gn, 20" barrel. Roughly 10% below max pressure.
What powder out of interest as that’s a lot from a 20” barrel! If RS60 / RL17 quick load definitely over estimates things.
True velocities do vary from the QL estimate. I have some that fall short, but others that exceed the estimate by some margin
QL estimates circa 2790fps for the load I use. It crono's at 2875fps, and this is after having to drop the original charge, because the accuracy went off, and I found the velocity had increased, once the barrel had run in.
This load is 42gn RS60, 2.825", 143gn ELD-X. 24" barrel. Tiktac T3X.
The "theoretical" load for the 20", 140gn ELD-M, 2.825", 48.9gn RL26, based on highest, safe barrel time, as a starting point.
Interesting stuff. For what it's worth I have a 20" CTR in 6.5 CM. I'd be very interested to know what QL says about a couple of powders I've used, in terms of ideal barrel time. First off is Viht N550. I was underwhelmed by its velocities, barely making it over 2450 at 38gr, behind a 143gr ELD-X, but it was supremely accurate, and the other is Norma URP. 41.7 grains of that behind some 140 ELD-Ms and it just about managed 2650. I take it from your post that the shorter barrel length makes a difference in terms of "safe" loads?I can only say what QL suggest, we know the data can be inaccurate, but not always.
My data is backed up using the Ballistic AE app, to shoot out to 920yds, with each distance being within a couple of .1 mrad clicks.
I can't say anything else about the 20" barrel, other than I'm not prepared to chop 4"' off mine, to find out for you![]()
I can only say what QL suggest, we know the data can be inaccurate, but not always.
My data is backed up using the Ballistic AE app, to shoot out to 920yds, with each distance being within a couple of .1 mrad clicks.
I can't say anything else about the 20" barrel, other than I'm not prepared to chop 4"' off mine, to find out for you![]()