- Joined
- Dec 31, 2005
- Messages
- 2,984
On the 6.5 Grendel upper I looked at Alexander Arms who are the original partners on the Grendel design and also Precision Firearms who make IMO an even better product for the money. On Alexander's site their top of the line barrels fitted with an upper are a lot more than Precision Firearms who are using two really good names of Dan Lilja and Les Baer. What both share in common is that they jump from a 20 inch barrel to a 24 inch and don't do a 22 inch. Alexander does do shorter barrels in the 16 to 18 inch range. Missing out a 22 inch offering may be due to a reason ... long VLD bullets such as the 130g 6.5mm rounds with a tight twist of 1-8 can be sensitive to barrel length "combinations" ... and work best in certain lengths. 24 inches gives 3 complete turns on the bullet prior to exit ... 20 inch gives 2.5 ... I suspect those bullets work best in a half twist increment for stability. Bullet choice is great in the 120g to 130g bracket for long range use but on an AR15 platform you have a pressure limitation because of the action/bolt set up compared to a bolt gun but the velocities are still very impressive from looking at the ballistic tables which in the case of the ones I looked at are based on a 24 inch barrel.
My experience of the AR15 platform is pretty extensive but solely in a military context where getting in and out of vehicles and FIBUA issues can dictate a great deal as to what barrel lengths are suitable. Hence my initial thoughts at 16 to 18 inches.
If you want it for Hunting though, which you did say was the case, then looking at the accuracy being obtained from the Les Baer 24 inch barrels on the Precision Firearms Neptune V upper ... less than .25 MOA at 100yds and less than .5 MOA at 220yds is VERY impessive ... better than many top .308 tactical bolt guns ... infact it makes a good case for whether you need anything else!!
Alexander does reasonably cheap factory ammo now ... but also does good Lapua based ammo too ... so you can mix hunting and target work accordingly. Plus the Lapua brass will be excellent for reloading as the pressures you are shooting at will give great extended life to the case ... if at a later date you go down that route.
The 130g Norma bullet is a favourite of mine ... great BC and able to give good velocity of 2500 plus out of a 24 inch barrel ... which will take you "accurately" to 600yds and possibly 800yds ... and you will hit steel at 1000yds. With tweaked handloads it might well group well at 1000yds. You can push the Lapua 123g Scenar or Sierra 123g HPBT 2650FPS and that may well be a better choice in an AR platform for long range because of the better velocity. If you don't go for an incline rail and use straight mounts then you definately want a scope with 100 MOA or more internal movement if you want to try shooting at 1000 yrds. You don't want to be right at the top of the scopes movement ideally as that is where windage limitations on the movement come into effect and yet it is exactly where you need maximum windage when shooting at distance.
I have'nt checked out the velocity sacrifice for a 20 inch barrel but would expect 100 fps on a 4 inch difference ... personally if you were thinking of 22 inches and can get a good 22 inch upper that might be fine ... but from doing a little reading around I am very taken with the performance offered by the 24 inch barrels. Woodchucks at 300 yards will be well within the rifles capabilities ... on target ammo I think 600 yards is do-able. Punching paper or steel out to 800yds and 1000yds is also there ... so you have a great all round set up. I was quite impressed with the "stats" once I got into the 6.5 Grendel cartridge in an AR15 ... would'nt mind trying one myself if I get the chance.
My experience of the AR15 platform is pretty extensive but solely in a military context where getting in and out of vehicles and FIBUA issues can dictate a great deal as to what barrel lengths are suitable. Hence my initial thoughts at 16 to 18 inches.
If you want it for Hunting though, which you did say was the case, then looking at the accuracy being obtained from the Les Baer 24 inch barrels on the Precision Firearms Neptune V upper ... less than .25 MOA at 100yds and less than .5 MOA at 220yds is VERY impessive ... better than many top .308 tactical bolt guns ... infact it makes a good case for whether you need anything else!!
Alexander does reasonably cheap factory ammo now ... but also does good Lapua based ammo too ... so you can mix hunting and target work accordingly. Plus the Lapua brass will be excellent for reloading as the pressures you are shooting at will give great extended life to the case ... if at a later date you go down that route.
The 130g Norma bullet is a favourite of mine ... great BC and able to give good velocity of 2500 plus out of a 24 inch barrel ... which will take you "accurately" to 600yds and possibly 800yds ... and you will hit steel at 1000yds. With tweaked handloads it might well group well at 1000yds. You can push the Lapua 123g Scenar or Sierra 123g HPBT 2650FPS and that may well be a better choice in an AR platform for long range because of the better velocity. If you don't go for an incline rail and use straight mounts then you definately want a scope with 100 MOA or more internal movement if you want to try shooting at 1000 yrds. You don't want to be right at the top of the scopes movement ideally as that is where windage limitations on the movement come into effect and yet it is exactly where you need maximum windage when shooting at distance.
I have'nt checked out the velocity sacrifice for a 20 inch barrel but would expect 100 fps on a 4 inch difference ... personally if you were thinking of 22 inches and can get a good 22 inch upper that might be fine ... but from doing a little reading around I am very taken with the performance offered by the 24 inch barrels. Woodchucks at 300 yards will be well within the rifles capabilities ... on target ammo I think 600 yards is do-able. Punching paper or steel out to 800yds and 1000yds is also there ... so you have a great all round set up. I was quite impressed with the "stats" once I got into the 6.5 Grendel cartridge in an AR15 ... would'nt mind trying one myself if I get the chance.
Very happy, seems to be about right as a package for most of the hunting I do. You have to decide what you want out of the rifle I guess.
I love that I have this group of guys with there vast knowledge and are willing to share what they know.