looking at buying a RRA .308 varmint upper is there any advantage in going with the 26" over the 20"
thanks
thanks
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20" or 26" .308 ar upper
- Thread starter josey wales
- Start date
Re: 20" or 26" ar upper
I bought a dpms 24" bull barrel and hated it, it was just too heavy. I just had it turned down to .750 and cut to 18", now I feel it is much more practical and it also shoots a smaller group than before. Thats just me but if anything go for the 20" over the 26". Good luck and enjoy!
I bought a dpms 24" bull barrel and hated it, it was just too heavy. I just had it turned down to .750 and cut to 18", now I feel it is much more practical and it also shoots a smaller group than before. Thats just me but if anything go for the 20" over the 26". Good luck and enjoy!
Re: 20" or 26" ar upper
The 20" is going to be easier to carry around for hunting, and the velocity that you do loose from going with a shorter barrel you'll probably never miss. I could be wrong, but I believe you'll lose around 30fps per inch of barrel, so around 180fps on average.
The 20" is going to be easier to carry around for hunting, and the velocity that you do loose from going with a shorter barrel you'll probably never miss. I could be wrong, but I believe you'll lose around 30fps per inch of barrel, so around 180fps on average.
Re: 20" or 26" ar upper
Josey Wales, if you get anything over a 20" barrel, you'll be kicking yourself in the ass everytime you take that thing to the range because it's going to wear you out having to lug it around.
Josey Wales, if you get anything over a 20" barrel, you'll be kicking yourself in the ass everytime you take that thing to the range because it's going to wear you out having to lug it around.
Re: 20" or 26" ar upper
More velocity. Also, I thought their uppers were unique to their lowers...
More velocity. Also, I thought their uppers were unique to their lowers...
Re: 20" or 26" ar upper
Like folks have already said, with a longer barrel, you will increase your muzzle velocity (but not likely a huge amount...law of diminishing returns). In turn, by getting a slight amount of additional muzzle velocity, you can also extend the max effective range of the rifle/cartridge (but again...not much in the case of the .308).
I would opt for a 20" at the longest for any semi-auto .308, and depending on the max ranges you intend to shoot and whether the rifle will be used for paper punching, hunting, etc., I would probably go shorter.
Like folks have already said, with a longer barrel, you will increase your muzzle velocity (but not likely a huge amount...law of diminishing returns). In turn, by getting a slight amount of additional muzzle velocity, you can also extend the max effective range of the rifle/cartridge (but again...not much in the case of the .308).
I would opt for a 20" at the longest for any semi-auto .308, and depending on the max ranges you intend to shoot and whether the rifle will be used for paper punching, hunting, etc., I would probably go shorter.
Re: 20" or 26" ar upper
I have been wondering the same thing, I am torn between a 20 and a 24 inch. I have found sources that say anything over 20 has no affect in velocity, then others that say 30fps per inch and one that claimed 50fps. My got feeling is that longer will always affect the velocity to some extent. Mine will mainly be for paper and I would like to shoot it at 1000 so I think I am going to do the 24.
I have been wondering the same thing, I am torn between a 20 and a 24 inch. I have found sources that say anything over 20 has no affect in velocity, then others that say 30fps per inch and one that claimed 50fps. My got feeling is that longer will always affect the velocity to some extent. Mine will mainly be for paper and I would like to shoot it at 1000 so I think I am going to do the 24.
Re: 20" or 26" ar upper
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: crackerbacks</div><div class="ubbcode-body">Mine will mainly be for paper and I would like to shoot it at 1000 so I think I am going to do the 24. </div></div>
You absolutely do NOT need a 24" barrel to get to 1k effectively with a .308! 20" will do the job just fine (and many do it with even shorter barrels than that)...I regularly shoot my POF P-308 20" out to 1k with good results.
Now, with that said, if from the safe to the truck and then the truck to the firing line is all the further you'll be carrying your rifle, then the 24" tube really doesn't hurt anything and you probably won't notice the inconvenience of the added weight/length. However, if you are planning on toting the rifle around, do yourself a favor and go shorter than 24".
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: crackerbacks</div><div class="ubbcode-body">Mine will mainly be for paper and I would like to shoot it at 1000 so I think I am going to do the 24. </div></div>
You absolutely do NOT need a 24" barrel to get to 1k effectively with a .308! 20" will do the job just fine (and many do it with even shorter barrels than that)...I regularly shoot my POF P-308 20" out to 1k with good results.
Now, with that said, if from the safe to the truck and then the truck to the firing line is all the further you'll be carrying your rifle, then the 24" tube really doesn't hurt anything and you probably won't notice the inconvenience of the added weight/length. However, if you are planning on toting the rifle around, do yourself a favor and go shorter than 24".
Re: 20" or 26" ar upper
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ORD</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: crackerbacks</div><div class="ubbcode-body">Mine will mainly be for paper and I would like to shoot it at 1000 so I think I am going to do the 24. </div></div>
You absolutely do NOT need a 24" barrel to get to 1k effectively with a .308! 20" will do the job just fine (and many do it with even shorter barrels than that)...I regularly shoot my POF P-308 20" out to 1k with good results.
Now, with that said, if from the safe to the truck and then the truck to the firing line is all the further you'll be carrying your rifle, then the 24" tube really doesn't hurt anything and you probably won't notice the inconvenience of the added weight/length. However, if you are planning on toting the rifle around, do yourself a favor and go shorter than 24". </div></div>
If you don't mind me asking, what bullet and at what velocity are you shooting out of the POF?
I already have a standard weight 18" upper if im gonna be hiking anywhere, but I like the idea of a heavy 20" if it performs well.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ORD</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: crackerbacks</div><div class="ubbcode-body">Mine will mainly be for paper and I would like to shoot it at 1000 so I think I am going to do the 24. </div></div>
You absolutely do NOT need a 24" barrel to get to 1k effectively with a .308! 20" will do the job just fine (and many do it with even shorter barrels than that)...I regularly shoot my POF P-308 20" out to 1k with good results.
Now, with that said, if from the safe to the truck and then the truck to the firing line is all the further you'll be carrying your rifle, then the 24" tube really doesn't hurt anything and you probably won't notice the inconvenience of the added weight/length. However, if you are planning on toting the rifle around, do yourself a favor and go shorter than 24". </div></div>
If you don't mind me asking, what bullet and at what velocity are you shooting out of the POF?
I already have a standard weight 18" upper if im gonna be hiking anywhere, but I like the idea of a heavy 20" if it performs well.
Re: 20" or 26" ar upper
I run several different loads from my POF (including FGMM and BH factory and my reloads), but my new pet bullets are the 155gr Lapua Scenars at approx. 2750fps (I pushed hotter and slower than that and ended up with an accuracy load at that velocity). I also shoot 175gr SMKs out of it at approx. 2550fps (don't have my specific numbers in front of me here at work).
I run several different loads from my POF (including FGMM and BH factory and my reloads), but my new pet bullets are the 155gr Lapua Scenars at approx. 2750fps (I pushed hotter and slower than that and ended up with an accuracy load at that velocity). I also shoot 175gr SMKs out of it at approx. 2550fps (don't have my specific numbers in front of me here at work).
Re: 20" or 26" .308 ar upper
thanks for all the info,i'am not worried about weight as i'am only going to play at the range with it.i wanted to find out about the velocity and accuracy difference between 20" and 26" bbl out to about 500 or 600 yards
thanks jason
thanks for all the info,i'am not worried about weight as i'am only going to play at the range with it.i wanted to find out about the velocity and accuracy difference between 20" and 26" bbl out to about 500 or 600 yards
thanks jason
Re: 20" or 26" .308 ar upper
If we were talking a cartridge that requires slow powders then there would be a point to 26" barrel - something like a 25-06, 270, . . ., etc. Best example in a somewhat commercial cartridge is the 257 Weatherby Magnum - it makes good use of 26".
Powders for 308 Winchester are just not that slow. It reasonably benefits from no more than a 22" barrel.
Keep in mind shorter barrels are stiffer, and will tend to be more accurate than longer ones though each is a law unto itself.
If we were talking a cartridge that requires slow powders then there would be a point to 26" barrel - something like a 25-06, 270, . . ., etc. Best example in a somewhat commercial cartridge is the 257 Weatherby Magnum - it makes good use of 26".
Powders for 308 Winchester are just not that slow. It reasonably benefits from no more than a 22" barrel.
Keep in mind shorter barrels are stiffer, and will tend to be more accurate than longer ones though each is a law unto itself.
Re: 20" or 26" .308 ar upper
20" it is,just ordered a .308 20" varmint upper from rra.
thanks for all help
now to find a scope
20" it is,just ordered a .308 20" varmint upper from rra.
thanks for all help
now to find a scope
Re: 20" or 26" .308 ar upper
Accuracy is accuracy in my book, a 20" can be just as accurate as a 26", sure the 20" is going to give you less muzzle velocity, but good data and range estimation will do a lot to negate that. So unless you are shooting alot of unknown distance targets I'd go with the 20". I personally prefer an 18".
Accuracy is accuracy in my book, a 20" can be just as accurate as a 26", sure the 20" is going to give you less muzzle velocity, but good data and range estimation will do a lot to negate that. So unless you are shooting alot of unknown distance targets I'd go with the 20". I personally prefer an 18".
Re: 20" or 26" .308 ar upper
a LWRC repr with a 16" and a leupold mark4 shooting 175gr mk will reach out to 875yards with no moa base or ring advantage . the 20" will be good out to 950yards at least. and will be a lot easer to pack around .the mark4 had 51 moa the way it was mounted
a LWRC repr with a 16" and a leupold mark4 shooting 175gr mk will reach out to 875yards with no moa base or ring advantage . the 20" will be good out to 950yards at least. and will be a lot easer to pack around .the mark4 had 51 moa the way it was mounted
Re: 20" or 26" .308 ar upper
I must be the only one to disgaree in this application on barrel length. I believe go as long as you can if you can get away with it (portability, manueverability).
If you are not humping the thing around, length and weight should not be a problem.
200 fps difference can mean <span style="font-style: italic">a lot</span> the longer distance you get prolonging the instability of trans sonic effects.
Barrel length Vs. Muzzle velocity (Test rifle Rem 700 SA)
Using a Federal GMM 168 gr-
<span style="text-decoration: underline">Barrel Length___Velocity____Velocity Loss FPS__Cumulative FPS</span>
26".................2594
25".................2654.......40 fps................40 fps
24".................2616.......38 fps................78 fps
23".................2592.......24 fps...............102 fps
22".................2572.......20 fps...............122 fps
21".................2566........6 fps...............128 fps
20".................2524.......42 fps...............170 fps
19".................2509.......15 fps...............185 fps
18".................2477.......32 fps...............217 fps
17".................2426.......51 fps...............268 fps
16".................2414.......12 fps...............280 fps
Courtesy Mike Lau,Texas Brigade Armory, Author <span style="font-style: italic">The Military and Police Sniper</span>
I must be the only one to disgaree in this application on barrel length. I believe go as long as you can if you can get away with it (portability, manueverability).
If you are not humping the thing around, length and weight should not be a problem.
200 fps difference can mean <span style="font-style: italic">a lot</span> the longer distance you get prolonging the instability of trans sonic effects.
Barrel length Vs. Muzzle velocity (Test rifle Rem 700 SA)
Using a Federal GMM 168 gr-
<span style="text-decoration: underline">Barrel Length___Velocity____Velocity Loss FPS__Cumulative FPS</span>
26".................2594
25".................2654.......40 fps................40 fps
24".................2616.......38 fps................78 fps
23".................2592.......24 fps...............102 fps
22".................2572.......20 fps...............122 fps
21".................2566........6 fps...............128 fps
20".................2524.......42 fps...............170 fps
19".................2509.......15 fps...............185 fps
18".................2477.......32 fps...............217 fps
17".................2426.......51 fps...............268 fps
16".................2414.......12 fps...............280 fps
Courtesy Mike Lau,Texas Brigade Armory, Author <span style="font-style: italic">The Military and Police Sniper</span>
Re: 20" or 26" .308 ar upper
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WARDOG</div><div class="ubbcode-body">Courtesy Mike Lau,Texas Brigade Armory, Author <span style="font-style: italic">The Military and Police Sniper</span> </div></div>That's a good book, but it's a bit dated now. Back then, with the old issue ammo, Mike was saying get a 26" barrel in a bolt gun to maximize velocity if that's the ammo you have to shoot. The context of the OP is quite different, and the question itself takes on different variables when one is talking about a gas gun.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WARDOG</div><div class="ubbcode-body">Courtesy Mike Lau,Texas Brigade Armory, Author <span style="font-style: italic">The Military and Police Sniper</span> </div></div>That's a good book, but it's a bit dated now. Back then, with the old issue ammo, Mike was saying get a 26" barrel in a bolt gun to maximize velocity if that's the ammo you have to shoot. The context of the OP is quite different, and the question itself takes on different variables when one is talking about a gas gun.
Re: 20" or 26" .308 ar upper
Additionally...
With the longer barrel, you will be able to experiment <span style="font-style: italic">more </span>with heavier bullets and slower burning powders to get to long-range accurately.
Many of you may be better shooters than I, however, I just don't see how you can get to 1000 yards consistently with a 18" barrel in .308.
Additionally...
With the longer barrel, you will be able to experiment <span style="font-style: italic">more </span>with heavier bullets and slower burning powders to get to long-range accurately.
Many of you may be better shooters than I, however, I just don't see how you can get to 1000 yards consistently with a 18" barrel in .308.
Re: 20" or 26" .308 ar upper
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WARDOG</div><div class="ubbcode-body">Additionally... With the longer barrel, you will be able to experiment <span style="font-style: italic">more </span>with heavier bullets and slower burning powders to get to long-range accurately.</div></div>Again, probably not so much with a gas gun.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WARDOG</div><div class="ubbcode-body">Additionally... With the longer barrel, you will be able to experiment <span style="font-style: italic">more </span>with heavier bullets and slower burning powders to get to long-range accurately.</div></div>Again, probably not so much with a gas gun.
Re: 20" or 26" .308 ar upper
I don't experiment with a whole lot of different types of ammo. I shoot M118LR. Its cost for me is free 99. If I have time I run it through a concentricity guage.
I will tell you that we consistently shoot accuratly well into subsonic with all of our sub MOA 7.62x51mm guns. And our 16" OBRs will ring 12" plates at 1000 meters all day long.
I agree higher muzzle velocity will give you an advantage on unknown distance targets. But when portability and manueverability are key longer barrels are a pain.
I don't experiment with a whole lot of different types of ammo. I shoot M118LR. Its cost for me is free 99. If I have time I run it through a concentricity guage.
I will tell you that we consistently shoot accuratly well into subsonic with all of our sub MOA 7.62x51mm guns. And our 16" OBRs will ring 12" plates at 1000 meters all day long.
I agree higher muzzle velocity will give you an advantage on unknown distance targets. But when portability and manueverability are key longer barrels are a pain.
Re: 20" or 26" .308 ar upper
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WARDOG</div><div class="ubbcode-body">
however, I just don't see how you can get to 1000 yards consistently with a 18" barrel in .308.</div></div>
Simple,
Don't use 168gr ammo, which is not well suited for shooting to 1000 under most conditions as well it doesn't transition as well from supersonic to subsonic.
My 16" GAP Semi Auto only needs 39MOA to 1000 yard with M118LR, at sea level under average conditions.
Chronographing a Larue OBR this week with the new Mk316 Mod 0, another military 175gr SMK offering, the MV was equal that a 20" KAC Mk11 Mod 2 shooting M118LR, so you are hovering just around 2600fps with a 175gr SMK out of a 16" Semi Auto .
Welcome to 2011... enjoy the fact we have better bullets, barrels and powders.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WARDOG</div><div class="ubbcode-body">
however, I just don't see how you can get to 1000 yards consistently with a 18" barrel in .308.</div></div>
Simple,
Don't use 168gr ammo, which is not well suited for shooting to 1000 under most conditions as well it doesn't transition as well from supersonic to subsonic.
My 16" GAP Semi Auto only needs 39MOA to 1000 yard with M118LR, at sea level under average conditions.
Chronographing a Larue OBR this week with the new Mk316 Mod 0, another military 175gr SMK offering, the MV was equal that a 20" KAC Mk11 Mod 2 shooting M118LR, so you are hovering just around 2600fps with a 175gr SMK out of a 16" Semi Auto .
Welcome to 2011... enjoy the fact we have better bullets, barrels and powders.
Re: 20" or 26" ar upper
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: crackerbacks</div><div class="ubbcode-body">I have been wondering the same thing, I am torn between a 20 and a 24 inch. I have found sources that say anything over 20 has no affect in velocity, then others that say 30fps per inch and one that claimed 50fps. My got feeling is that longer will always affect the velocity to some extent. Mine will mainly be for paper and I would like to shoot it at 1000 so I think I am going to do the 24. </div></div>
My Brothers Light Remmy sporter, and my 12-Ftr.
We have about a 200 FPS dif. (20" VS 30")
This is with a fl sized load.(45.0 Varget/168 A-Maxx, Lapua)
He can get better with his formed loads, but they don't fit in mine.
We share seating dies.
Wilson and Forester ultra.
Both are set the same, we do not change them.
We use one to check the other.
Runout is usually less than .0015.
His I can carry, mine I need a truck!
Sorry to stray.
Wanting to build a 26" upper myself.
Two clips are easier to carry than a 100 round box.
If you are thinking about a can, you might want to go short.
If you are thinking of adding a brake, it will make it longer.
Think about how you want to carry.
See what fits there.
Why pay for longer only to pay again to have it cut off?
I'm still leaning towards longer.
Thanks
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: crackerbacks</div><div class="ubbcode-body">I have been wondering the same thing, I am torn between a 20 and a 24 inch. I have found sources that say anything over 20 has no affect in velocity, then others that say 30fps per inch and one that claimed 50fps. My got feeling is that longer will always affect the velocity to some extent. Mine will mainly be for paper and I would like to shoot it at 1000 so I think I am going to do the 24. </div></div>
My Brothers Light Remmy sporter, and my 12-Ftr.
We have about a 200 FPS dif. (20" VS 30")
This is with a fl sized load.(45.0 Varget/168 A-Maxx, Lapua)
He can get better with his formed loads, but they don't fit in mine.
We share seating dies.
Wilson and Forester ultra.
Both are set the same, we do not change them.
We use one to check the other.
Runout is usually less than .0015.
His I can carry, mine I need a truck!
Sorry to stray.
Wanting to build a 26" upper myself.
Two clips are easier to carry than a 100 round box.
If you are thinking about a can, you might want to go short.
If you are thinking of adding a brake, it will make it longer.
Think about how you want to carry.
See what fits there.
Why pay for longer only to pay again to have it cut off?
I'm still leaning towards longer.
Thanks
Re: 20" or 26" ar upper
I know I am not trying to suggest a 16" or 18" 308 can compete against a longer in something like F/TR or competitions of that nature. However in a field rifle there is no reason to carry longer or honestly go beyond 24" in a 308. It really doesn't make sense nowadays.
We just received a new load from Cor Bon that is going 2770fps out of my 22" Valkyrie, with a 175gr -- that is hauling. In the field most aren't going to shoot to 1000 yards and those that are, usually find themselves above sea level. So anything you loose in barrel length you gain in elevation.
The 308 was not designed to shoot a 1000 yards, we do it because we can, but really it is an 800m cartridge. In todays' world with things like the 178gr Superformance from Hornady, you have a 178gr bullet that will go 2800+ out of standard factory rifle. Bring that down to a 20" and you are still over 2600fps, which gets you anywhere you want to go.
Now competition is a different animal, these guys are generally pushing a 155gr to 2950fps which essentially turns it into a 260 or something to that effect. So you cannot compare what an F Class or F/TR shooter is doing versus a field shooter. But the key, they walk from the car to the line back to the car and can have a nice little wheeled cart with them to haul their stuff.
People like to know what others are doing, well Terry Cross managed a Top 10 at the Fall Shooter's Bash with an 18" 308... it can be done providing you know what you are doing. A short barrel 308 is not meant for new shooters, however you don't need to go 26" anymore either... 22" is optimal, 24" if you feel the need.
Bullet selection matters, a 168gr is not well suited for shooting far, a 175gr, 178gr or even 180VLD is much better suited for LR. If you plan on shooting past 600 yards regardless of the reason, consider the bullet, it matters, along with velocity. The key to best 1120fps at the target, 1200fps is even better.
I know I am not trying to suggest a 16" or 18" 308 can compete against a longer in something like F/TR or competitions of that nature. However in a field rifle there is no reason to carry longer or honestly go beyond 24" in a 308. It really doesn't make sense nowadays.
We just received a new load from Cor Bon that is going 2770fps out of my 22" Valkyrie, with a 175gr -- that is hauling. In the field most aren't going to shoot to 1000 yards and those that are, usually find themselves above sea level. So anything you loose in barrel length you gain in elevation.
The 308 was not designed to shoot a 1000 yards, we do it because we can, but really it is an 800m cartridge. In todays' world with things like the 178gr Superformance from Hornady, you have a 178gr bullet that will go 2800+ out of standard factory rifle. Bring that down to a 20" and you are still over 2600fps, which gets you anywhere you want to go.
Now competition is a different animal, these guys are generally pushing a 155gr to 2950fps which essentially turns it into a 260 or something to that effect. So you cannot compare what an F Class or F/TR shooter is doing versus a field shooter. But the key, they walk from the car to the line back to the car and can have a nice little wheeled cart with them to haul their stuff.
People like to know what others are doing, well Terry Cross managed a Top 10 at the Fall Shooter's Bash with an 18" 308... it can be done providing you know what you are doing. A short barrel 308 is not meant for new shooters, however you don't need to go 26" anymore either... 22" is optimal, 24" if you feel the need.
Bullet selection matters, a 168gr is not well suited for shooting far, a 175gr, 178gr or even 180VLD is much better suited for LR. If you plan on shooting past 600 yards regardless of the reason, consider the bullet, it matters, along with velocity. The key to best 1120fps at the target, 1200fps is even better.
Re: 20" or 26" ar upper
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: "Wardog"</div><div class="ubbcode-body">however, I just don't see how you can get to 1000 yards consistently with a 18" barrel in .308.</div></div>
http://www.sniperschool.com/sniper-rifle-barrel-length
then
http://www.sniperschool.com/barrel-length-revisited
GPS cuts ALL of their rifles to 18". They see absolutely no fall off in the ability to do long range shooting. None.
It was because of these articles that I decided to go with a 20" 308.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: "Wardog"</div><div class="ubbcode-body">however, I just don't see how you can get to 1000 yards consistently with a 18" barrel in .308.</div></div>
http://www.sniperschool.com/sniper-rifle-barrel-length
then
http://www.sniperschool.com/barrel-length-revisited
GPS cuts ALL of their rifles to 18". They see absolutely no fall off in the ability to do long range shooting. None.
It was because of these articles that I decided to go with a 20" 308.
Re: 20" or 26" ar upper
I have a 19" Terry Cross gun that shoots the 178 amax to 1k. I switched over to the 155 scenar and it will go to the 1k line this weekend. Since it is going 2890 fps @ 47 degrees, i have no doubt that it will reach 1k easily. I am having to run it hot to get these velocities, but I will probably go with a 18"-20" barrel again when I burn this one up because it is so nice when shooting positional.
I have a 19" Terry Cross gun that shoots the 178 amax to 1k. I switched over to the 155 scenar and it will go to the 1k line this weekend. Since it is going 2890 fps @ 47 degrees, i have no doubt that it will reach 1k easily. I am having to run it hot to get these velocities, but I will probably go with a 18"-20" barrel again when I burn this one up because it is so nice when shooting positional.
Re: 20" or 26" ar upper
I didn't mean it to seem that way.
Just wanted to give our .308 bolt data.
Thinking about building a 6.5 in a 15.
I got to see the brown Santa deliver some early stocks.
Terry does one heck of a job.
.260 is all that is needed.
if you want to carry, think about that first.
I didn't mean it to seem that way.
Just wanted to give our .308 bolt data.
Thinking about building a 6.5 in a 15.
I got to see the brown Santa deliver some early stocks.
Terry does one heck of a job.
.260 is all that is needed.
if you want to carry, think about that first.
Re: 20" or 26" ar upper
I can see what you are basing your claims on for short barrel, 1k yards.
155 Scenars at 2950 fps is smokin'
as well as the 175 out of a 22" bbl at 2770 fps.
I subscribe to GPS and the article a while back about "Sawzall-ing" a barrel at the range and crownin it from a wooden bench had me cringing.
I would like to know what powder CorBon is using to launch the 175 at 2770 fps. I never tried 175 smk's out of my 16" AR-10(T). When I was developing a handload I stuck with the 168 SMK's to eek out enough velocity to stay at MACH out to 900 yds. I ran into a wall with accuracy falling quickly at 2720 fps using Varget. I had to back off to 2660 fps to maintain accuracy. With the 2660 fps the math indicates I still have 100 fps in MACH but field results showed key holing at 900 yds, 3500 elev.
I haven't concentrated on reloading the .308 in about 2 years, focusing more on .30 and 7mm short mags which give much better performance with accuracy and exterior ballistics.
Perhaps I need to update my learnin' on the reloading the modern .308 bullets.
I can see what you are basing your claims on for short barrel, 1k yards.
155 Scenars at 2950 fps is smokin'
as well as the 175 out of a 22" bbl at 2770 fps.
I subscribe to GPS and the article a while back about "Sawzall-ing" a barrel at the range and crownin it from a wooden bench had me cringing.
I would like to know what powder CorBon is using to launch the 175 at 2770 fps. I never tried 175 smk's out of my 16" AR-10(T). When I was developing a handload I stuck with the 168 SMK's to eek out enough velocity to stay at MACH out to 900 yds. I ran into a wall with accuracy falling quickly at 2720 fps using Varget. I had to back off to 2660 fps to maintain accuracy. With the 2660 fps the math indicates I still have 100 fps in MACH but field results showed key holing at 900 yds, 3500 elev.
I haven't concentrated on reloading the .308 in about 2 years, focusing more on .30 and 7mm short mags which give much better performance with accuracy and exterior ballistics.
Perhaps I need to update my learnin' on the reloading the modern .308 bullets.
Re: 20" or 26" ar upper
Why isn't there any focus on the barrel ? Surely barrel quality and tightness are a material consideration in being able to drop length and not performance ? How tight can / should a 18-20" be to max distance vs say SAAMI or other specs. Just trying to understand what else to consider beyond the length/bullet combo ?
Why isn't there any focus on the barrel ? Surely barrel quality and tightness are a material consideration in being able to drop length and not performance ? How tight can / should a 18-20" be to max distance vs say SAAMI or other specs. Just trying to understand what else to consider beyond the length/bullet combo ?
Re: 20" or 26" ar upper
A .298 or .299 tight bore will maximize the velocity of factory ammo, but it will also get you to max pressure quicker. There's no free lunch, but that is why the .308 is an ideal all-around performer.
A .298 or .299 tight bore will maximize the velocity of factory ammo, but it will also get you to max pressure quicker. There's no free lunch, but that is why the .308 is an ideal all-around performer.
Re: 20" or 26" ar upper
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WARDOG</div><div class="ubbcode-body">
I would like to know what powder CorBon is using to launch the 175 at 2770 fps.</div></div>
High quality barrel? Also I would imagine that a crimp on the bullet and a crimped-in primer would make a little more pressure. While you can buy brass that is pre-primed with crimped primers and cannelured match bullets on occasion 99% of reloaders I don't think are using either. Also most reloaders load in such a way that they can re-use their brass several times safely. That's why I think when reloaders try to "dupe" a hot factory round at home they can never quite seem to do it 100% without hitting pressure.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WARDOG</div><div class="ubbcode-body">
I would like to know what powder CorBon is using to launch the 175 at 2770 fps.</div></div>
High quality barrel? Also I would imagine that a crimp on the bullet and a crimped-in primer would make a little more pressure. While you can buy brass that is pre-primed with crimped primers and cannelured match bullets on occasion 99% of reloaders I don't think are using either. Also most reloaders load in such a way that they can re-use their brass several times safely. That's why I think when reloaders try to "dupe" a hot factory round at home they can never quite seem to do it 100% without hitting pressure.
Re: 20" or 26" ar upper
You can't load for a bolt and put those in a gas mag.
(Very light neck tension)
Trying to take great info from the paper Guys might not work.
I have seen many different brass come out of .308 gas guns
Some is Damn near pefect, while others can just be squeezed
through generic dies.
As Frank said, we do it because we can.
Gotta weigh the trade-offs.
Don't need .308 to do 500 and under.
Ar-15 replaces my shotgun for many things.
Wish I had the AR-10.
20 inch should be a good choice for that upper.
You can't load for a bolt and put those in a gas mag.
(Very light neck tension)
Trying to take great info from the paper Guys might not work.
I have seen many different brass come out of .308 gas guns
Some is Damn near pefect, while others can just be squeezed
through generic dies.
As Frank said, we do it because we can.
Gotta weigh the trade-offs.
Don't need .308 to do 500 and under.
Ar-15 replaces my shotgun for many things.
Wish I had the AR-10.
20 inch should be a good choice for that upper.
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