What caliber to use for 600 yards when keeping barrel length under 21'' ?

[HopeToBe]

This might be an odd question, but still I give it a try.

Reason for asking is that we have a local variety of F-class shooting were I live (not in the US) and we have quite strict restrictions on weight, basically meaning I need to clear a 10.5 limit. After calculations this should allow a typical barrel of 21'' given my current set up, hence I wound what caliber to choose? This is normally shot at 600 yards.

My initial idea was 6BR but I wonder if that barrel length would be too short or not to properly take advantage of the cartridge or not? 6.5 grendel?

Any suggestion?

 

[dmoran65]

Maybe you will want to ask your question on the F-Class forum instead ( Benchrest.com - F-Class )
This is the 600/1000 Benchrest Forum.

On a note, most all F-Class rules world wide are 22-lb weight limits. Boy would it suck giving up all that velocity do to such a light weight rule, and not being able to take advantage of the long barrels with there added velocity and extra cooling effectis that go with Long Range (600/1000-BR, F-Class, Palma, etc..)
Good Luck,
Donovan Moran

 

[eggman]

This might be an odd question, but still I give it a try.

Reason for asking is that we have a local variety of F-class shooting were I live (not in the US) and we have quite strict restrictions on weight, basically meaning I need to clear a 10.5 limit. After calculations this should allow a typical barrel of 21'' given my current set up, hence I wound what caliber to choose? This is normally shot at 600 yards.

My initial idea was 6BR but I wonder if that barrel length would be too short or not to properly take advantage of the cartridge or not? 6.5 grendel?

Any suggestion?

I'm thinking your initial idea would be correct . The 6 BR would be hard to beat . However the 6.5 Grendel or 6/6.5 Grendel would work especially if you already have a PPC boltface. Stick with powders on the faster side for the shorter barrel . I'm thinking like maybe XBR 8208 or there abouts.

Good Luck,
Rodney

 

[VT52]

Who made up those rules?! Probably an LV shooter who can't stand competition?

For f-class you need something that will dodge the wind. A 6BR might be too sensitive. Barrel length doesn't really play into caliber choice, as your limited to 22" as well. A 6x47 or 6.5-284 would be a safer choice, pushing bullets hard to get everything out of those 20-something inches. 6.5grendel does not do as well as a 6BR, so that would be counter productive, as is the 6AR (6mm-6.5Grendel). But it all depends on what boltface you have.

 

[dmoran65]

Who made up those rules?! Probably an LV shooter who can't stand competition?

For f-class you need something that will dodge the wind. A 6BR might be too sensitive. Barrel length doesn't really play into caliber choice, as your limited to 22" as well. A 6x47 or 6.5-284 would be a safer choice, pushing bullets hard to get everything out of those 20-something inches. 6.5grendel does not do as well as a 6BR, so that would be counter productive, as is the 6AR (6mm-6.5Grendel). But it all depends on what boltface you have.

With having to be less then 10.5-lb's to make his weight limit, wouldn't a 6.5-284 be a "arm full" of recoil ?

 

[expiper]

go light

Id try a 6 BR with a 25" Hunter profile bbl,,,and a 36 leu scope ...lots of the Montana shooters make the their light class (11 lb) tht way,,,,just gota shave weight ,,,I have a 10 lb hunter gun that could do it....and use 90 gr bulllets with Rx-15 !!! just a sugestion from an ole' hillbilly<<<Roger

 

[Rich De]

One of my shooting buddies had bought, by mistake, a 1 - 8 twist 6mm Palma contour barrel. When he got it, it was supposed to be a HV taper (that's another story) but he decided to keep it anyway. I had mentioned once about the story at the "Houston Ware house" and the supposed ideal length for the PPC being 21 3/4" So he got to thinking and asked me to cut it and chamber it for the 6mmBR. Which I did! He has found very little difference in the velocity ( I am not going to quote as I don't know the exact numbers but less than 100 fps) between his 28" 6mmBR. It is also very accurate. So, it will work! And he has used it in 600 yd. BR.
Rich De

 

[walkinhorseman]

First choice for me would be an 1-8" twist 6BR shooting the 105-107 out to 600 yards. Second would be a 6.5x47 Lapua, then the 6.5 Creedmoor, both 1-8" twist. The Lapua has the edge on the brass. After 600 yards, the 6.5's might give you an edge. I can't see the 6.5x284 until you need to go to 1000 yards and wind is a factor.