1-7 or 1-9 twist..WHICH IS BETTER for AR-M4?? I have a 1/9 on my Bushy and the groups are about baseball size at 50 yrds with ACOG ta33-8. My RRA has a 1/7 and the groups at 50 yrds are quarter size with my irons. I am thinking I am shaky with the ACOG because sometimes I can hold a tighter grop than a "baseball" size group. I "plink" with 55 gr. federal or remington. Nothing too expensive since I only hunt beer/soda cans, steel, and paper. Would the twist difference have anything to do with the groups since I am shooting the same ammo from both?
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1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
- Thread starter Bullseyelr
- Start date
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
Neither one is necessarily "better"...just different. It depends on what you want to shoot out of it. The twist is determinative of how heavy a round you can stabilize from the rifle.
1:9 will stabilize up to approx. 69gr (some will do slightly heavier bullets, but YMMV) and will also work on lighter 40-45gr bullets. It is plenty for shooting 55gr ball ammo.
1:7 will stabilize just about any heavier bullet, including 75gr, 77gr, and even 80gr bullets, but is generally not as effective with the lighter offerings.
Neither one is necessarily "better"...just different. It depends on what you want to shoot out of it. The twist is determinative of how heavy a round you can stabilize from the rifle.
1:9 will stabilize up to approx. 69gr (some will do slightly heavier bullets, but YMMV) and will also work on lighter 40-45gr bullets. It is plenty for shooting 55gr ball ammo.
1:7 will stabilize just about any heavier bullet, including 75gr, 77gr, and even 80gr bullets, but is generally not as effective with the lighter offerings.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster.
1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
Which bullet are you wanting to shoot?
I have a 1:9 on my Bushmaster but it's really the redheaded step child (no offense to any red headed step children on this board) of my rifle inventory. I've lost interest in it and like bolt guns better myself.
That said, mine shoots a 55 gr Hornady FMJ very well. I use mine for plinking mostly. I ring steel with it but I'm not shooting past 300 yds with it.
Which bullet are you wanting to shoot?
I have a 1:9 on my Bushmaster but it's really the redheaded step child (no offense to any red headed step children on this board) of my rifle inventory. I've lost interest in it and like bolt guns better myself.
That said, mine shoots a 55 gr Hornady FMJ very well. I use mine for plinking mostly. I ring steel with it but I'm not shooting past 300 yds with it.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ORD</div><div class="ubbcode-body">1:7 will stabilize just about any heavier bullet, including 75gr, 77gr, and even 80gr bullets, but is generally not as effective with the lighter offerings. </div></div>
How so? I fire 45, 50, and 55gr out of my 1-in-7 LMTs all of the time to the exact same effect as the heavier bullets.
Seriously, I know I only have 20 some odd posts here but if there's one thing I know a lot of it's AR patterned rifles.
http://www.m4carbine.net
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ORD</div><div class="ubbcode-body">1:7 will stabilize just about any heavier bullet, including 75gr, 77gr, and even 80gr bullets, but is generally not as effective with the lighter offerings. </div></div>
How so? I fire 45, 50, and 55gr out of my 1-in-7 LMTs all of the time to the exact same effect as the heavier bullets.
Seriously, I know I only have 20 some odd posts here but if there's one thing I know a lot of it's AR patterned rifles.
http://www.m4carbine.net
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
I wasn't referring to 45gr loads. Many 45gr loads will work okay in the 1:7...optimally, the heavier bullets will perform better in a tighter twist barrel. I was referring more to the light loads such as 36gr to 40gr, but I just didn't "splain" it very well...my fault.
I wasn't referring to 45gr loads. Many 45gr loads will work okay in the 1:7...optimally, the heavier bullets will perform better in a tighter twist barrel. I was referring more to the light loads such as 36gr to 40gr, but I just didn't "splain" it very well...my fault.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
No down side for the 1 in 7. I wouldn't buy anything else for my AR. Nothing wrong w/ 1 in 9, but why not be sure you can shoot anything through it. Good luck.
No down side for the 1 in 7. I wouldn't buy anything else for my AR. Nothing wrong w/ 1 in 9, but why not be sure you can shoot anything through it. Good luck.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
I agree with ORD, lighter bullets wouldn't work as well with 1:7 twist if you're shooting them at long distance; like 500 yards and up. The grouping would most likely fly apart, but there's not many bullets under 50 grain that I would want to shoot that far anyway.
I agree with ORD, lighter bullets wouldn't work as well with 1:7 twist if you're shooting them at long distance; like 500 yards and up. The grouping would most likely fly apart, but there's not many bullets under 50 grain that I would want to shoot that far anyway.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
personally i would go with the 1:9 twist...your accuracy will suffer with a light grain bullet 60 grains or less and a 1:7 twist..they really are designed for 75-90 grain. this comes from first hand experience in my 3 precision long range ar's...
personally i would go with the 1:9 twist...your accuracy will suffer with a light grain bullet 60 grains or less and a 1:7 twist..they really are designed for 75-90 grain. this comes from first hand experience in my 3 precision long range ar's...
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
Carbine and precision AR don't generally go hand-in-hand IME.
Said another way. Apples are to Oranges as Carbines are to precision long range AR's.
Carbine and precision AR don't generally go hand-in-hand IME.
Said another way. Apples are to Oranges as Carbines are to precision long range AR's.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
I would go with the 7 twist. With the .223/5.56 it is just a better all around twist rate and allows you to use the heavier high BC bullets if you so choose.
However, you have to be careful when going up from there, cartridge wise. I had a 22-250AI with a 8 twist and it wouldn't shoot the 40-45 grain pills. It was simply too fast and when the projectile exited the muzzle it grenaded. It couldn't handle the RPMs. I would suspect a 22-250 and 22BR would do the same, at least with the 40gr pills.
I would go with the 7 twist. With the .223/5.56 it is just a better all around twist rate and allows you to use the heavier high BC bullets if you so choose.
However, you have to be careful when going up from there, cartridge wise. I had a 22-250AI with a 8 twist and it wouldn't shoot the 40-45 grain pills. It was simply too fast and when the projectile exited the muzzle it grenaded. It couldn't handle the RPMs. I would suspect a 22-250 and 22BR would do the same, at least with the 40gr pills.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
Like other have said I would look at going with a 1/7 twist. I use that on my AR's but that is my preferance and that is what I have been using ever since I joined the military. That is the twist rate that we use and it has just stuck on me and that is why I just dont see me going with anything slower.
I tend to stay with the 62gr round as that is also what we shoot which is the M855 round. The 1/7 was first designed to be able to stabailize the M856 tracer rounds.
Here is some info for you just to give you an idea:
Special purpose rifles often have uncommon twist rates. For example, if you are building a varmint rifle and want to shoot the short 35 grain, 40 grain, and 50 grain bullets, a 1:12, or even 1:14 twist would be best. On the other hand, long range High Power shooters often select 1:8, 1:7.7, 1:7, or 1:6.5-twist barrels to stabilize the long 77, 80 and even 90 grain bullets used for 1,000 yard competition. Additionally, new testing of heavier rounds (68-77 grains) seems to show that they perform very well in simulated tissue and may be a better defensive choice than 55 grain or 62 grain rounds. The majority of shooters, though, typically shoot bullets of 50 to 69 grains in weight (note that the 62gr SS-109/M855 bullet is as long as a 71 grain lead core bullet) and should select 1:9 twist barrels. At typical .223 velocities, a 1:9 twist will stabilize bullet lengths equivalent to lead-core bullets of 40 to 73 grains in weight.
1:12 twist rifles cannot stabilize SS-109/M855 bullets and 1:7 twist rifles are slightly less accurate with lighter bullets and will often blow apart the thin jackets of lightweight varmint bullets. The 1:7 twist is used by the military to stabilize the super-long L-110/M856 tracer bullet out to 800 yards, but unless your plans include shooting a significant amount of M856, the 1:9 twist rate is better suited for general use.
There is, of course, an exception: if you want to use loads utilizing the heavier, 75-77 grain match bullets currently used by Spec-Ops troops and other selected shooters, you'll want a 1:7 twist barrel. Although military loadings using these bullets are expensive and hard to get, some persistent folks have managed to obtain a supply, and will need the proper barrel twist to use them. Anyone who foresees a need to shoot this ammo should consider a 1:7 twist barrel.
Yes I copied and pasted.
Like other have said I would look at going with a 1/7 twist. I use that on my AR's but that is my preferance and that is what I have been using ever since I joined the military. That is the twist rate that we use and it has just stuck on me and that is why I just dont see me going with anything slower.
I tend to stay with the 62gr round as that is also what we shoot which is the M855 round. The 1/7 was first designed to be able to stabailize the M856 tracer rounds.
Here is some info for you just to give you an idea:
Special purpose rifles often have uncommon twist rates. For example, if you are building a varmint rifle and want to shoot the short 35 grain, 40 grain, and 50 grain bullets, a 1:12, or even 1:14 twist would be best. On the other hand, long range High Power shooters often select 1:8, 1:7.7, 1:7, or 1:6.5-twist barrels to stabilize the long 77, 80 and even 90 grain bullets used for 1,000 yard competition. Additionally, new testing of heavier rounds (68-77 grains) seems to show that they perform very well in simulated tissue and may be a better defensive choice than 55 grain or 62 grain rounds. The majority of shooters, though, typically shoot bullets of 50 to 69 grains in weight (note that the 62gr SS-109/M855 bullet is as long as a 71 grain lead core bullet) and should select 1:9 twist barrels. At typical .223 velocities, a 1:9 twist will stabilize bullet lengths equivalent to lead-core bullets of 40 to 73 grains in weight.
1:12 twist rifles cannot stabilize SS-109/M855 bullets and 1:7 twist rifles are slightly less accurate with lighter bullets and will often blow apart the thin jackets of lightweight varmint bullets. The 1:7 twist is used by the military to stabilize the super-long L-110/M856 tracer bullet out to 800 yards, but unless your plans include shooting a significant amount of M856, the 1:9 twist rate is better suited for general use.
There is, of course, an exception: if you want to use loads utilizing the heavier, 75-77 grain match bullets currently used by Spec-Ops troops and other selected shooters, you'll want a 1:7 twist barrel. Although military loadings using these bullets are expensive and hard to get, some persistent folks have managed to obtain a supply, and will need the proper barrel twist to use them. Anyone who foresees a need to shoot this ammo should consider a 1:7 twist barrel.
Yes I copied and pasted.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
I would recommend the 1-7 twist.
I have a 1-9 twist, it works for me, but I don't go heavier than 75 grains. If you are thinking SPR type, with improved accuracy, get the Wylde chamber. Safe for 5.56, more accurae with 5.56 and .223. Most varmint guns/barrels are .223 only.
SOME (as in very few) 1-9 twists will stabilize the 77 grain. The safest bet is either 1-7 or 1-8 for 77 grain bullets (which is your MK262 loads).
I do not share many folks disdain of bushmaster, I have seen many of them work with thousands of rounds through them with nary a hitch. (I'm talking police academy and military instruction) Literally, thousands of rounds. They are accurate, dependable and well made.
Are there better ones?
Yes. (I'm partial to my S&W)
If I were going into combat, in a hostile environment, were I would be shooting various types of mil-spec ammo in massive quantities, would I choose another brand over Bushmaster?
Again, yes.
But for the average , or even above average owner, where you might put 2 or 3 thousand rounds a year through your rifle, a bushmaster is fine.
But there is nothing wrong with spending the extra cash on a better AR either.
I would recommend the 1-7 twist.
I have a 1-9 twist, it works for me, but I don't go heavier than 75 grains. If you are thinking SPR type, with improved accuracy, get the Wylde chamber. Safe for 5.56, more accurae with 5.56 and .223. Most varmint guns/barrels are .223 only.
SOME (as in very few) 1-9 twists will stabilize the 77 grain. The safest bet is either 1-7 or 1-8 for 77 grain bullets (which is your MK262 loads).
I do not share many folks disdain of bushmaster, I have seen many of them work with thousands of rounds through them with nary a hitch. (I'm talking police academy and military instruction) Literally, thousands of rounds. They are accurate, dependable and well made.
Are there better ones?
Yes. (I'm partial to my S&W)
If I were going into combat, in a hostile environment, were I would be shooting various types of mil-spec ammo in massive quantities, would I choose another brand over Bushmaster?
Again, yes.
But for the average , or even above average owner, where you might put 2 or 3 thousand rounds a year through your rifle, a bushmaster is fine.
But there is nothing wrong with spending the extra cash on a better AR either.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
I also vote for the 7 twist over the 9 twist. The most common of the bullets people shoot are the 55 grain ones, and they'll both shoot them fine, but the 7 twist will allow you to shoot the 70+ grain stuff that the 9 twist most likely won't stabilize.
I also vote for the 7 twist over the 9 twist. The most common of the bullets people shoot are the 55 grain ones, and they'll both shoot them fine, but the 7 twist will allow you to shoot the 70+ grain stuff that the 9 twist most likely won't stabilize.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
FWIW, I have seen 1-7 that would not shoot 55 grain pills worth a shit, but 62's and up, very accurate.
FWIW, I have seen 1-7 that would not shoot 55 grain pills worth a shit, but 62's and up, very accurate.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
My 1-7 shoots better groups with my 55 gr. ammo than my 1-9, but the groups with my 1-9 arent bad either. I think I shake alittle. Also, there is nothing wrong with the Busmasters. Sure some people see them as "middle of the road" AR's but I have had mine for 10 years, 2k rounds through it and NOT ONE malfunction. I would take it anywhere and bet my life on it. It has a custom upper but factory barrel. My RRA is also is a good rifle and never had an issue with it. I figured that the epople who drop $$$$ on the more expensive AR's can do so if they like..personal preference..but I am not going to war and they are for plinking so no need to spend 1500.00 ++ for an AR....when I can use the extra $$ for good optics (EOTech & magnifier....ACOG). Plus I like to drop the $$ into my precision bolt guns....the others are just for plinking.
My 1-7 shoots better groups with my 55 gr. ammo than my 1-9, but the groups with my 1-9 arent bad either. I think I shake alittle. Also, there is nothing wrong with the Busmasters. Sure some people see them as "middle of the road" AR's but I have had mine for 10 years, 2k rounds through it and NOT ONE malfunction. I would take it anywhere and bet my life on it. It has a custom upper but factory barrel. My RRA is also is a good rifle and never had an issue with it. I figured that the epople who drop $$$$ on the more expensive AR's can do so if they like..personal preference..but I am not going to war and they are for plinking so no need to spend 1500.00 ++ for an AR....when I can use the extra $$ for good optics (EOTech & magnifier....ACOG). Plus I like to drop the $$ into my precision bolt guns....the others are just for plinking.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
1 in 7 let's you do anything you need to do with an M4/AR, maybe not absolutely optimal with everything, but passable. 1 in 9 works well in the middle of the weight range and begins absolutely sucking as you get to or past 75grs depending on the barrel.
1 in 7 let's you do anything you need to do with an M4/AR, maybe not absolutely optimal with everything, but passable. 1 in 9 works well in the middle of the weight range and begins absolutely sucking as you get to or past 75grs depending on the barrel.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dvdt</div><div class="ubbcode-body">Which bullet are you wanting to shoot?
I have a 1:9 on my Bushmaster but it's really the redheaded step child (no offense to any red headed step children on this board) of my rifle inventory. I've lost interest in it and like bolt guns better myself.
That said, mine shoots a 55 gr Hornady FMJ very well. I use mine for plinking mostly. I ring steel with it but I'm not shooting past 300 yds with it. </div></div>
If shit were to ever hit the fan, I'd bet your favor would shift back post haste.
I too prefer bolt guns in that I enjoy shooting them more, but make no mistake, if SHTF I reach for my Dynamic Double Star Duo (and by that I mean my Double Star AR 15 and DS 1911) before any of my bolt guns.
BTW: If you plan on shooting heavy pills (over 70 grains give or take) go 1:7. If the budget box of PMC 55 grain bullets are all your rifle will see, a 1:9 is more than adequate.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dvdt</div><div class="ubbcode-body">Which bullet are you wanting to shoot?
I have a 1:9 on my Bushmaster but it's really the redheaded step child (no offense to any red headed step children on this board) of my rifle inventory. I've lost interest in it and like bolt guns better myself.
That said, mine shoots a 55 gr Hornady FMJ very well. I use mine for plinking mostly. I ring steel with it but I'm not shooting past 300 yds with it. </div></div>
If shit were to ever hit the fan, I'd bet your favor would shift back post haste.
I too prefer bolt guns in that I enjoy shooting them more, but make no mistake, if SHTF I reach for my Dynamic Double Star Duo (and by that I mean my Double Star AR 15 and DS 1911) before any of my bolt guns.
BTW: If you plan on shooting heavy pills (over 70 grains give or take) go 1:7. If the budget box of PMC 55 grain bullets are all your rifle will see, a 1:9 is more than adequate.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
As dumb as it sound, I use xm193 55 gr. ammo...NO PMC...and I am not going to use heavier bullets...just plinking..I am telling you...if SHTF, I would have NO PROBLEM trusting my Bushmaster or RRA....Bolt gun would be 2nd choice but it would come along too....I really dont shoot the 2 AR's. They are for my kids....All I am really interested in is my 2 precision bolt guns....just got a thought to ask the question.
As dumb as it sound, I use xm193 55 gr. ammo...NO PMC...and I am not going to use heavier bullets...just plinking..I am telling you...if SHTF, I would have NO PROBLEM trusting my Bushmaster or RRA....Bolt gun would be 2nd choice but it would come along too....I really dont shoot the 2 AR's. They are for my kids....All I am really interested in is my 2 precision bolt guns....just got a thought to ask the question.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
One makers twist does not equal another's. Since it's an issue for you, I'd run a rod through it and measure, so you know. Likewise with chambers: some say 5.56 when they're actually not. Nor do all makers use the same gas port diameter... So what I'm saying is there are probably other factors than twist contributing to the difference in accuracy. Have you swapped lowers? Similar triggers?
I find my 1:7 twist Noveske N4 plenty accurate with 55 grain xm193, although it's chrome-lined, only 16", and with standard plastic handguards. It's also only got irons and a mil-spec trigger, but when I'm on the ball I keep it under an inch at 50.
One makers twist does not equal another's. Since it's an issue for you, I'd run a rod through it and measure, so you know. Likewise with chambers: some say 5.56 when they're actually not. Nor do all makers use the same gas port diameter... So what I'm saying is there are probably other factors than twist contributing to the difference in accuracy. Have you swapped lowers? Similar triggers?
I find my 1:7 twist Noveske N4 plenty accurate with 55 grain xm193, although it's chrome-lined, only 16", and with standard plastic handguards. It's also only got irons and a mil-spec trigger, but when I'm on the ball I keep it under an inch at 50.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
I have a 1/7 twisted Noveske bbl carbine(16"),W/3-9that will shoot .6 MOA with 77smk,bhm,factory load out to 500 yards.but will only do 1.0/1.1 MOA with 55grn BT's/Fed premium.In the past I had a Bushy "V" Max,W/1-9 twist W/3.5-10 that would shoot those Fed.Pre.55 BT's to.5 MOA. As always,choose your bullet,then your cartridge,then your gun.Some shit matters!
I have a 1/7 twisted Noveske bbl carbine(16"),W/3-9that will shoot .6 MOA with 77smk,bhm,factory load out to 500 yards.but will only do 1.0/1.1 MOA with 55grn BT's/Fed premium.In the past I had a Bushy "V" Max,W/1-9 twist W/3.5-10 that would shoot those Fed.Pre.55 BT's to.5 MOA. As always,choose your bullet,then your cartridge,then your gun.Some shit matters!
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: neoinarien</div><div class="ubbcode-body">neither.
get 1/8</div></div>
I was wondering when someone was going to say that. I read all the way to the bottom and finally someone said it - 1/8 twist - the perfect compromise.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: neoinarien</div><div class="ubbcode-body">neither.
get 1/8</div></div>
I was wondering when someone was going to say that. I read all the way to the bottom and finally someone said it - 1/8 twist - the perfect compromise.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
I have two 1/7 twist on a 20" AR and a 16" AR as well as mutliple 1/9 twist and 18", 7" and 16". I cannot really tell the difference in standard 55 grain bullets. With heavier bullets, the 1/7 is quite accurate for what I use it for (plinking up to 300m).
I have two 1/7 twist on a 20" AR and a 16" AR as well as mutliple 1/9 twist and 18", 7" and 16". I cannot really tell the difference in standard 55 grain bullets. With heavier bullets, the 1/7 is quite accurate for what I use it for (plinking up to 300m).
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JSTARSZ</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: neoinarien</div><div class="ubbcode-body">neither.
get 1/8</div></div>
I was wondering when someone was going to say that. I read all the way to the bottom and finally someone said it - 1/8 twist - the perfect compromise. </div></div>
Listen to JSTARSZ, he obviously knows what he's talking about.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JSTARSZ</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: neoinarien</div><div class="ubbcode-body">neither.
get 1/8</div></div>
I was wondering when someone was going to say that. I read all the way to the bottom and finally someone said it - 1/8 twist - the perfect compromise. </div></div>
Listen to JSTARSZ, he obviously knows what he's talking about.
G
Guest
Guest
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bullseyelr</div><div class="ubbcode-body">1-7 or 1-9 twist..WHICH IS BETTER for AR-M4?? I have a 1/9 on my Bushy and the groups are about baseball size at 50 yrds with ACOG ta33-8. My RRA has a 1/7 and the groups at 50 yrds are quarter size with my irons. I am thinking I am shaky with the ACOG because sometimes I can hold a tighter grop than a "baseball" size group. I "plink" with 55 gr. federal or remington. Nothing too expensive since I only hunt beer/soda cans, steel, and paper. Would the twist difference have anything to do with the groups since I am shooting the same ammo from both? </div></div>
No, with 55gr it won't make a difference in accuracy. It doesn't seem like you're running much of a solid experiment. Try testing them side by side on a bench/rest and both with the ACOG.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bullseyelr</div><div class="ubbcode-body">1-7 or 1-9 twist..WHICH IS BETTER for AR-M4?? I have a 1/9 on my Bushy and the groups are about baseball size at 50 yrds with ACOG ta33-8. My RRA has a 1/7 and the groups at 50 yrds are quarter size with my irons. I am thinking I am shaky with the ACOG because sometimes I can hold a tighter grop than a "baseball" size group. I "plink" with 55 gr. federal or remington. Nothing too expensive since I only hunt beer/soda cans, steel, and paper. Would the twist difference have anything to do with the groups since I am shooting the same ammo from both? </div></div>
No, with 55gr it won't make a difference in accuracy. It doesn't seem like you're running much of a solid experiment. Try testing them side by side on a bench/rest and both with the ACOG.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JSTARSZ</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: neoinarien</div><div class="ubbcode-body">neither.
get 1/8</div></div>
I was wondering when someone was going to say that. I read all the way to the bottom and finally someone said it - 1/8 twist - the perfect compromise. </div></div>
Actually, I mentioned it in my first response.
Just sayin!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JSTARSZ</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: neoinarien</div><div class="ubbcode-body">neither.
get 1/8</div></div>
I was wondering when someone was going to say that. I read all the way to the bottom and finally someone said it - 1/8 twist - the perfect compromise. </div></div>
Actually, I mentioned it in my first response.
Just sayin!
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: decodeddiesel</div><div class="ubbcode-body">1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster. </div></div>
This.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: decodeddiesel</div><div class="ubbcode-body">1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster. </div></div>
This.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: decodeddiesel</div><div class="ubbcode-body">1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster.</div></div>
Anything particularly bad about dpms and bushmaster?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: decodeddiesel</div><div class="ubbcode-body">1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster.</div></div>
Anything particularly bad about dpms and bushmaster?
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
In my experience, DMPS makes really crappy LPKs. I thought bushys were ok...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: palmik</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: decodeddiesel</div><div class="ubbcode-body">1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster.</div></div>
Anything particularly bad about dpms and bushmaster? </div></div>
In my experience, DMPS makes really crappy LPKs. I thought bushys were ok...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: palmik</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: decodeddiesel</div><div class="ubbcode-body">1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster.</div></div>
Anything particularly bad about dpms and bushmaster? </div></div>
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: M.45</div><div class="ubbcode-body">In my experience, DMPS makes really crappy LPKs. I thought bushys were ok...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: palmik</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: decodeddiesel</div><div class="ubbcode-body">1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster.</div></div>
Anything particularly bad about dpms and bushmaster? </div></div> </div></div>
I've bought two DPMS LPK's, and both have worked fine. I replaced a bunch of parts with ambidextrous parts, but that was preference and not out of necessity.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: M.45</div><div class="ubbcode-body">In my experience, DMPS makes really crappy LPKs. I thought bushys were ok...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: palmik</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: decodeddiesel</div><div class="ubbcode-body">1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster.</div></div>
Anything particularly bad about dpms and bushmaster? </div></div> </div></div>
I've bought two DPMS LPK's, and both have worked fine. I replaced a bunch of parts with ambidextrous parts, but that was preference and not out of necessity.
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
Have you used other LPKs other than DMPS? The two DMPS parts kits were much more cheaply made than the RRA kits I've used. It was really apparent that they cut a lot of corners with cheaper metals and less attention to the details (fit and finish).
I'd never buy a DMPS kit again. I've also heard their rifles are lackluster as well but since I wouldn't buy one, I wouldn't know.
Again, it's just my experience. I still have one of the parts kits in a lower and it hasn't failed yet. Then again it's only got 200 rounds thru it.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Adician</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: M.45</div><div class="ubbcode-body">In my experience, DMPS makes really crappy LPKs. I thought bushys were ok...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: palmik</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: decodeddiesel</div><div class="ubbcode-body">1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster.</div></div>
Anything particularly bad about dpms and bushmaster? </div></div> </div></div>
I've bought two DPMS LPK's, and both have worked fine. I replaced a bunch of parts with ambidextrous parts, but that was preference and not out of necessity. </div></div>
Have you used other LPKs other than DMPS? The two DMPS parts kits were much more cheaply made than the RRA kits I've used. It was really apparent that they cut a lot of corners with cheaper metals and less attention to the details (fit and finish).
I'd never buy a DMPS kit again. I've also heard their rifles are lackluster as well but since I wouldn't buy one, I wouldn't know.
Again, it's just my experience. I still have one of the parts kits in a lower and it hasn't failed yet. Then again it's only got 200 rounds thru it.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Adician</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: M.45</div><div class="ubbcode-body">In my experience, DMPS makes really crappy LPKs. I thought bushys were ok...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: palmik</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: decodeddiesel</div><div class="ubbcode-body">1 in 7 hands down. There is really no down side whats so ever to 1 in 7. It will stabilize everything from 45gr varmint rounds all the way up to 77gr MK262 rounds.
With a 1 in 9 you may not be able to stabilize the heavier rounds which not only have superior external ballistics, but also have superior terminal ballistics.
Also make double damn sure it has a 4150 steel barrel that is HPT/MPI and a bolt that is HPT/MPI and shot peened. I would look at a carbine from Daniels Defense, Colt, LMT, Bravo Company, Noveske, or Sabre. These brands have a reputation for reliability and durability. Steer clear of DPMS, Olympic, and Bushmaster.</div></div>
Anything particularly bad about dpms and bushmaster? </div></div> </div></div>
I've bought two DPMS LPK's, and both have worked fine. I replaced a bunch of parts with ambidextrous parts, but that was preference and not out of necessity. </div></div>
Re: 1-7 or 1-9 twist..WHICH IS BETTER for AR-M4??
My advice is going to be different than the others. I own far too many of the black rifles and have had a pile more so I got a chance to waste a lot of money on them.
All but one of mine is A2 with 16 or 20" barrel and all have 1:9 twist but one. The BushMaster 1:8 has fired some of the best match scores of my life using 69 grain bullets. The rifle has done Master level at 200 and Expert at 600. It also shot the worst butt whupping of my match career using 55 grain bullets at 600 yards! 1:8 is very marginal with 55 grain bullets at 200. At 600 yards, the 55 grain is terrible in that tube.
55 grain loads are the most common .223 so I recommend 1:9 twist because that will handle the 69 grain match favorites and the 55 grain slugs real well.
Twist rate is all about bullet weight. As the bullet gets heavier, it can't grow in diameter so it gets longer. The fast twist is needed for the heavier (longer) slugs. It's not a "one size fits all" deal. You pick what bullet you want to shoot and that selects the correct twist rate. Just don't expect the rifle to shoot other bullet weights well.
1:9 is an excellent compromise that will pick up the 55 grain and 69 grain favorites.
Flash
My advice is going to be different than the others. I own far too many of the black rifles and have had a pile more so I got a chance to waste a lot of money on them.
All but one of mine is A2 with 16 or 20" barrel and all have 1:9 twist but one. The BushMaster 1:8 has fired some of the best match scores of my life using 69 grain bullets. The rifle has done Master level at 200 and Expert at 600. It also shot the worst butt whupping of my match career using 55 grain bullets at 600 yards! 1:8 is very marginal with 55 grain bullets at 200. At 600 yards, the 55 grain is terrible in that tube.
55 grain loads are the most common .223 so I recommend 1:9 twist because that will handle the 69 grain match favorites and the 55 grain slugs real well.
Twist rate is all about bullet weight. As the bullet gets heavier, it can't grow in diameter so it gets longer. The fast twist is needed for the heavier (longer) slugs. It's not a "one size fits all" deal. You pick what bullet you want to shoot and that selects the correct twist rate. Just don't expect the rifle to shoot other bullet weights well.
1:9 is an excellent compromise that will pick up the 55 grain and 69 grain favorites.
Flash
