20" carbine users - need your speeds for 6.5x47 + 260 + 7-08

[6.5BR]

Posted in hunting forum - but below is why I want to compare speeds. Thanks in advance for replies.

Ok gang - if you wanted to build an efficient deer/hog rifle in a 20" bbl, possible varmint weight, but none the less, a shorty, which round would you choose?

No need for a 308 for more recoil and figuring a 6mm would be less than ideal to get powder burn in a short bbl.

I know a 7 might outperform the 6.5 on the 308 case, but is blast much worse in those than a 47 in a shorty?

If blast is much less w/the 47, thinking it might be the ticket. My hunch is trajectory will be similar for 130s in the 6.5s vs 140 in the 7mm, shots typically will not be over 400yds, but unconcerned if I had to stretch a little more.

FWIW, I'd possible consider 21" but no more. Speed loss is not a concern for my use, handling is...and blast.

 

[tylerw02]

If speed isn't a concern, does it matter if its a 6mm, 6.5mm, 7mm, or .308? Just get a short .308 Win and a brake if speed doesn't matter.

 

[6.5BR]

Brakes are LOUD, Re: Speed, not concerned about the speed loss in a 20" in those rounds, as all will sling 120-140 bullets at 2700-2900 with BCs sufficient for my purpose.

 

[DAVETOOLEY]

I know a 7 might outperform the 6.5 on the 308 case, but is blast much worse in those than a 47 in a shorty?

Blast as you call it is a function of case capacity and barrel length. Every case you listed uses just about the same powder charge.

 

[tylerw02]

Brakes are LOUD, Re: Speed, not concerned about the speed loss in a 20" in those rounds, as all will sling 120-140 bullets at 2700-2900 with BCs sufficient for my purpose.

That's what hearing protection is for!

20" with 140s at 2700? Maybe? I got over 2700 with a 22" 6.5x47, but if speed doesn't matter...really going to come to your purpose. Just pick a round if speed doesn't matter, no reason to worry about the rest. How far do you intend to shoot?

ETA: my former 20" .260 was right around 2600 with 140s.

 

[MarinePMI]

Ever consider the 6x45mm?

 

[thespecialist]

Easy choice for me since I just had this debate with myself a few months back, go 260. My 20" runs 123's just a touch under 2900 and will push 140's up to 2750fps (as high as I went in testing, still saw no pressure signs) with H4350.

 

[wfjames22]

I am currently working on loads for my 20" 260 that I just got back from the smith about 2 weeks ago. So far I have been able to get about 2750fps with 140 amax's and about 2800fps with 130 Accubonds, both using H4350. I was hoping for a little more speed (closer to 2900fps) with the 130's but the last 5 shots at 100yds from Sunday with that load measured .439 ctc. As long as I can replicate those results consistently, that will be my hunting load for this rifle.

The 140 Amax load will be a lot of fun on steel/paper as well. I am only running those at 2825fps out of my 26" barreled 260 and it's a hammer as well. Both guns were put together by Chad Dixon and they both have 8.5 twist Brux tubes.

 

[6.5BR]

Thanks guys, Tooley, my thoughts were the 47 uses a tad less powder, and recoil/blast might be a touch lighter, Tyler - no doubt, I suffer tinnitus and use plugs + muffs Still HATE blast as much if not more than recoil. Never feel any need to beat myself up more than the job at hand, used a 6BR long ago to take my furthest deer at 400 yds, but it had a 26" tube, rather run a 22-23" minimum in that round w/8 ROT and Amaxs...

I do have ALOT of 6.5mm bullets at the moment, used many 260s and 6.5x55s as well as a 6.5-308 before the 260 was on the scene, yet contemplated a 47 as being perhaps closer in speed in a short carbine bbl to a 260. I know some say about 100 fps difference. It's not a big issue. I ran 2780 in a 22" Sako 260 w/130s and IMR 4350 but know H4350 will give about 2850, most claim 50-75 gain w/H vs IMR.

If running a 7/08 I could run 120 Barnes or Ballistic tips for less recoil than 140s and the Speer 130 is not a bad bullet either, but again having alot of 6.5 bullets, the choice leans on 6.5s if that alone. Never had a 47...so not sure what to expect w/one. Figure they run +/- about 5gr less powder.

Just wondering if I'd expect much noticeable difference. I ran two 21" 7/08s in past and they had a good bit of blast. That is more an issue when spending time on the range, and I do try to get some range time w/hunting rifles as well. Thanks again.

Edit - btw, Marine, I have owned a 6mm TCU, aka 6x45 improved, it's not quite the cartridge the other 3 are, but effective at lesser distances.

 

[Boltfluter]

6.5 x 47. Less powder equals less blast with the bonus of fitting in a mag better if you plan to run one. Just my .002. In reality they will all get the job done.

Regards,
Paul

 

[6.5BR]

Thanks Paul, Leaning that way, esp. since I am going this short, matter of blast and recoil keeping to a minimum.

 

[Rustystud]

7mm/08 with 20" barrel

I just completed a Model 7 Remington in 7mm/08 with a 20" FL barrel. It had a SAAMI Spec Chamber, Muller Works, 1:8.77 twist, 5R, barrel. I shot 140 Nosler Accuonds, 120 Barnes XXXMX, Barnes 140 XXX, and 150 Swift Sciroccos. The 120s with 45.gr Varget shot 2900 fps. The 140 Accubonds shot best with 44.5 gr Varget 2700fps. and The 150 Sciroccos shot best with 40.5 Varget 2575.

My 20" 308 Model 7 Remington with a 20", 5C, 1:12, shoots 150 Sciroccos at 2975 with 47.gr W-748.

I could not get the W-748 to shoot in the 7mm/08.

Nat Lambeth

 

[ddavis]

My 21" Creedmoor does 2800 with 130's, or 2730 with 140 Amax. With a naked barrel, the blast wasn't terrible, but wasn't pleasant either. I've never ran it with a brake, but I'm not a fan of them as I use my rifles for hunting as well. My solution was to get a suppressor. It reduces recoil, noise, and blast. If you go with a compact titanium model, the added length and weight won't be too bad.

 

[jbailey]

I have a 21" 6.5x47L and the recoil is not bad at all, especially for a hunting application. I was using it for 600yd and in matches and it does recoil a bit more than I would like, especially on movers, so I'm getting a mini-muscle brake for it.

MV (no pressure signs at all):
130gr JLK: 2800 (w/ H4350)
107gr SMK: 3000 (w/ RL15)

The 21" barrel is Rem Varmint contour which results in a rifle weight of 13lbs, considerably lighter than my 26" AMU contour barrel at 16lbs (I barrel swap, so the only difference are the barrels, same stock, scope, etc).

If you like 6.5BR, you will like the 6.5x47L cartridge. As easy to load, plus you get more MV. Enjoy!

 

[BoilerUP]

There are a handful of 16.5-18.5" 6.5x47Ls on this forum...

My 20" 260 barrel should arrive Monday; just need to decide if I want to replace my 26" barrel or build a whole new rifle around the 20" tube.

 

[6.5BR]

Good stuff guys, thanks. Nat, fyi, My former 7/08s - a 700 BDL SS and BDL Varmint, both chopped at 21" gave 3050-3100 47/Varget - 120s, and 2900-2950 - 45gr/140
that was partial sized RP brass, safe in my rifles, no certainty in others, but I believe I was within a grain of book max. Also, WW brass holds about 1.5gr more as I recall. Not had in a few years so never tried newer powders some use today.

Sounds pretty efficient w/the 47 and CM above. Thanks again.

 

[LongArm]

I am contemplating cutting my 260 from 25" (2860fps) to 20" (??FPS)

 

[Bo Ployhar]

My last 6.5x47 would push 130 vld's 2800 to 2820 at 20" with varget. New one is around 2750 with 140's at 22" and my wife's is a touch over 2900 with 130's at 22" both with varget, these barrels seem like they might be a little faster than the old one? Really fun round though!

 

[6.5BR]

Thanks for info Bo, what barrel and twist are you using sir, and any preferred primer choice?