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Posted: 6/3/2003 4:09:50 PM EDT
What Ya Think?

Which is better and Why ?

Thanks.
Link Posted: 6/3/2003 4:48:14 PM EDT
[#1]
[url]ammo-oracle.com[/url]
Link Posted: 6/3/2003 4:53:31 PM EDT
[#2]
Similar thread: [url]http://www.ar15.com/forums/topic.html?b=3&f=118&t=161802[/url]
Link Posted: 6/3/2003 6:00:02 PM EDT
[#3]
1/12. I never buy 62gn. ammo. Never going to. If the SHTF, Who is going to buy more exspensive 62gn. ammo over the 55 gn. stuff? if there is not any 55gn stuff, then I go down in weight, or get the 55gn. exspensive ammo. I doubt the "AMMO JUNCTION" will be open, you will probably have to goto wal mart, or Academy sports. Now someone says I cant use the "martial law's" ammo. Sure I can. When you pick up their ammo you get a free rifle included.
GG
Link Posted: 6/3/2003 6:03:57 PM EDT
[#4]
Link Posted: 6/3/2003 7:15:19 PM EDT
[#5]
Quoted:
Barrel Twist Trivia (I have been reading up!): Why were barrels changed from 1:14 to 1:12 for production M16s? (Probably too easy a question).
View Quote


Cold weather stabilization.......What do I win???? [:D]


1/7 is the most versatile twist. It handles everything from 55gr all the way up to the 100gr stuff.

1/12 is only good for anything up to 55gr. Unless you are building a varmint rig, stay away from the 1/12...at least go 1/9
Link Posted: 6/3/2003 7:34:35 PM EDT
[#6]
Quoted:
Barrel Twist Trivia (I have been reading up!): Why were barrels changed from 1:14 to 1:12 for production M16s? (Probably too easy a question).
View Quote


I knew that too!

I have a 1/7, and my next upper will be 1/7 also. For versatility.
Link Posted: 6/3/2003 7:37:55 PM EDT
[#7]
Link Posted: 6/3/2003 8:28:41 PM EDT
[#8]
If you are going to shoot 75/77 gr BTHPs, you should go 1/7. If you are going to shoot M193/M855 only, 1/9 is a good choice.
Link Posted: 6/3/2003 10:18:44 PM EDT
[#9]
There is no best or worst, it just all depends on what ammo you want to use. If it's 55 gr or lighter, the 1/12 twist of the SP1 will suffice. The 1/9 twist works well with bullets up through 69 (and maybe 73) grains. The 1/7 will likely be needed for bullets from the 75 gr range on up, although some 1/9 twist barrels will handle 75 and 77 gr ammo fairly well.

If you think there's ever a chance you will use a variety of ammo, then I would recommend the 1/7 twist simply because it will work with damn near any .223 round (except maybe the ultra-lightweight varmint bullets that will get shredded because of the fast twist rate).

I like the versatility of the 1/7 for my use because my favorite round for home defense is the 75 gr Hornady OTM load. However, if I want to drop down to 55 gr M193, I can do so without any problems, except a re-zero perhaps. But if you don't plan on shooting anything besides M193 or nothing heavier than 69 gr match stuff, the 1/9 may be most versatile for you.

-Charging Handle
Link Posted: 6/3/2003 10:22:41 PM EDT
[#10]
i've always been told that 1/7 is too fast for bullets under 58gr and could possibly cause them to spin apart once they lack the support of the barrel.

Never seen it myself, but i can't imagine a prefragmented bullet would be very effective.
Link Posted: 6/4/2003 5:23:15 AM EDT
[#11]
the 1-in-9 twist seems to like everything I've tried in it - of course, it was only 45 gr & 55 grain bullet weights.
Link Posted: 6/4/2003 6:28:08 AM EDT
[#12]
Quoted:
i've always been told that 1/7 is too fast for bullets under 58gr and could possibly cause them to spin apart once they lack the support of the barrel.
View Quote


Some bullets, like the Speer TNT will fly apart at high rotation rates.  Most of the really good bullets, V-Maxes, Ballistic Tips, Silvertips, etc, are good for as much velocity as you can give them in nearly any barrel.


Never seen it myself, but i can't imagine a prefragmented bullet would be very effective.
View Quote


I think every one experiences this differently, but the bullets don't always vaporize the instant they leave the barrel.
Link Posted: 6/4/2003 6:53:00 AM EDT
[#13]
It's been said time and again that to stabilize the heavier bullets you gots to have 1/7. Buuuuut think about it. Besides an AR15 what else on the face of the planet has that fast a twist besides superman on a swizzel stick with a case of the farts??????? I'll bet a dollar and a case of really cheap beer that 1/9 will do the job. Please.....don't tell me I'm wrong...PROVE to me that I'm wrong.
Link Posted: 6/4/2003 8:18:12 AM EDT
[#14]
Quoted:
It's been said time and again that to stabilize the heavier bullets you gots to have 1/7. Buuuuut think about it. Besides an AR15 what else on the face of the planet has that fast a twist besides superman on a swizzel stick with a case of the farts??????? I'll bet a dollar and a case of really cheap beer that 1/9 will do the job. Please.....don't tell me I'm wrong...PROVE to me that I'm wrong.
View Quote


OK, how about this:

Bushmaster 16" M4 1/9 barrel with Black Hills blue box 75gr... many shots never hit the paper at 100 yds, and the ones that did keyholed.

Colt 16" M4 1/7 barrel with the same ammo produced 1.5" groups.  No keyholes.

The twist rate does make a difference with weights over 69gr or so.

You need to read [url]www.ammo-oracle.com[/url]
Link Posted: 6/4/2003 9:14:30 AM EDT
[#15]
Bushmaster needs to start making 16" 1/7 barrels or some customers will buy ones from Colt!
Link Posted: 6/4/2003 10:10:33 AM EDT
[#16]
Dont forget CHROME LINED on those 1x7 barrels from Bushmaster.
Link Posted: 6/4/2003 11:17:32 AM EDT
[#17]
Quoted:
Bushmaster 16" M4 1/9 barrel with Black Hills blue box 75gr... many shots never hit the paper at 100 yds, and the ones that did keyholed.
View Quote


I had the same problem with my Bushmaster 1:9 14.5" M4 barrel.

After bringing it home and cleaning the snot out of it (it had been a while since it had a good cleaning with a bronze brush and Hoppes Copper remover) I tried again:

Group @ 50 yards: 2.125"
Group @100 yards: 3"
Group @200 yards: 8" (note at this range the target was smaller than the dot in my Reflex)

No sign of keyholing at any range (with 70 rounds of Black Hills 75gr Blue box fired total)

My groups also improved with SA 55gr ammo as well (from 3" to 2" @ 50 yards) after the scrubbing.  I'm thinking the copper build up was causing the accuraccy problems.  It had been at least 1000 rounds since the last 'good' cleaning with CLP & Otis, and several thousand since using copper remover (over the last 1000 rounds I just use CLP and a pass or two of the Bore Snake).  

If you give it a try I'd be interested in hear your results.
Link Posted: 6/4/2003 11:22:40 AM EDT
[#18]
To answer the orginal question:  1:7 is better because its more versitile.

I used to say 1:9 for its slightly longer life; however with the advent of the heavier bullets 1:7 will give you better accuraccy with them.

My 1:9 M4 will shoot the heavy rounds (see prev post) - but I get AK like accuracy.
Link Posted: 6/4/2003 11:26:36 AM EDT
[#19]
Quoted:
If you give it a try I'd be interested in hear your results.
View Quote


Actually, both barrels were brand new.  Only rounds put through them where for sighting in (about 20 through each).

It's also a fact that barrels aren't exactly what the twist rate says they are.  A 1/9 may actually be closer to a 1/8 or 1/10.  

I believe that's why the heavier bullets work in some 1/9's and not others.  Mine is probably closer to 1/10.
Link Posted: 6/4/2003 12:06:20 PM EDT
[#20]

Which Twist is Better = 1/7 or 1/9 ?
View Quote

Oh my. [:|]
Link Posted: 6/4/2003 12:23:32 PM EDT
[#21]
Quoted:
It's also a fact that barrels aren't exactly what the twist rate says they are.  A 1/9 may actually be closer to a 1/8 or 1/10.  
View Quote


I've heard that, but I have a hard time believing there is so much variance using modern production methods.

Hopefully there is a barrel maker (or one of the manufacturers) can help explain this possibility.
Link Posted: 6/4/2003 2:48:14 PM EDT
[#22]
Quoted:
It's been said time and again that to stabilize the heavier bullets you gots to have 1/7. Buuuuut think about it. Besides an AR15 what else on the face of the planet has that fast a twist besides superman on a swizzel stick with a case of the farts??????? I'll bet a dollar and a case of really cheap beer that 1/9 will do the job. Please.....don't tell me I'm wrong...PROVE to me that I'm wrong.
View Quote


That superman line made me almost made me pee in my pants, thanks
GG
Link Posted: 6/4/2003 7:22:59 PM EDT
[#23]
I seem to recall that 1/7 twist was required because of longer bullets, not heavier, and it is optimal for the extra long M856 tracer not the M855. I believe that if you could make a 100 grain bullet with the same size and shape of the M193 bullet and then you could use a 1/12 barrel and get good results.

Mack
Link Posted: 6/4/2003 7:53:00 PM EDT
[#24]
And what would that bullet be made of?  Uranium?!?!?  godd luck with aquiring radioactive materials bro.  Let me know how it works out for ya. [;)]
Link Posted: 6/4/2003 8:01:10 PM EDT
[#25]

Just curious here, why would you want to shoot 75gr ammo?  Stick w/ 55 or 62, IMHO
Link Posted: 6/4/2003 8:10:42 PM EDT
[#26]
Quoted:
If you think there's ever a chance you will use a variety of ammo, then I would recommend the 1/7 twist simply because it will work with damn near any .223 round (except maybe the ultra-lightweight varmint bullets that will get shredded because of the fast twist rate).
View Quote


To quote the Ammo Oracle . . .
"You can also overspin projectiles and cause overstability. This results in the not-so-desireable condition that keeps the nose of the round pointed high, as illustrated below:"

The 1/7 doesn't overspin a 55 grain?  How light do you have to go for a 1/7 to be too much?
Link Posted: 6/4/2003 8:18:32 PM EDT
[#27]
Another Great quote from the Ammo Oracle . . .

Question: Will M193 be accurate in a 1:7 or 1:9 twist barrel?

Answer:  It may be marginally less accurate due to the fast twist rate, particularly in 1:7 twist barrels.  A bullet's flight is disrupted slightly as it leaves the barrel and after traveling some distance, will "settle down" into an even spiral, similar to a thrown football.  The faster a bullet is spinning, the longer it takes to settle down.  The most accurate twist rate for any length of bullet will be just a bit faster than what is required to stabilize it for its entire flight path (1.3 SG).
Link Posted: 6/5/2003 8:06:39 AM EDT
[#28]
Quoted:

Just curious here, why would you want to shoot 75gr ammo?  Stick w/ 55 or 62, IMHO
View Quote


More accuracy and better terminal performance with the 75gr.
Link Posted: 6/5/2003 8:50:14 AM EDT
[#29]
Originally Posted By Gun Guru:
Quoted:
It's been said time and again that to stabilize the heavier bullets you gots to have 1/7. Buuuuut think about it. Besides an AR15 what else on the face of the planet has that fast a twist besides superman on a swizzel stick with a case of the farts??????? I'll bet a dollar and a case of really cheap beer that 1/9 will do the job. Please.....don't tell me I'm wrong...PROVE to me that I'm wrong.
View Quote


That superman line made me almost made me pee in my pants, thanks
GG
View Quote


Thanks GG!!!! Not everyone appreciates my hit or miss sense of humor(pun intended).
Link Posted: 6/5/2003 9:04:31 AM EDT
[#30]
Quoted:
Quoted:

Just curious here, why would you want to shoot 75gr ammo?  Stick w/ 55 or 62, IMHO
View Quote


More accuracy and better terminal performance with the 75gr.
View Quote


OK: 1)You're overspecializing the gun/ammo match to get that accuracy and I'm not convinced accuracy WILL be better than with a 69gr or a 64 gr etc.

2) Very few (if any) 75 gr bullets are going to be fmj so you're depending on soft points etc for tissue destruction. There aren't any 75 gr bullets with steel penetrator cores I'm aware of so It's not for penetration. Please see the ammo faq for discussions of 223 wound effect characteristics re: terminal effect in persons.

3) If you really want terminal effects better/deeper than most 223 loadings wouldn't it make more sense to go to a larger caliber?

Just my 2 cents.
Link Posted: 6/5/2003 9:18:55 AM EDT
[#31]
Quoted:
Quoted:
Quoted:

Just curious here, why would you want to shoot 75gr ammo?  Stick w/ 55 or 62, IMHO
View Quote


More accuracy and better terminal performance with the 75gr.
View Quote


OK: 1)You're overspecializing the gun/ammo match to get that accuracy and I'm not convinced accuracy WILL be better than with a 69gr or a 64 gr etc.
View Quote


Actually, accuracy IS better with the proper twist rate.  Ever notice that longe range match shooters use 75/77/80/90 gr bullets?

2) Very few (if any) 75 gr bullets are going to be fmj so you're depending on soft points etc for tissue destruction. There aren't any 75 gr bullets with steel penetrator cores I'm aware of so It's not for penetration. Please see the ammo faq for discussions of 223 wound effect characteristics re: terminal effect in persons.
View Quote


FMJ?  No, you're right.  They're OTM.  They penetrate well, and they fragment nicely.  Take a look at the Ammo Faq again, and look at the 75/77gr gelatin experiment tacked at the top of the ammo forum.

3) If you really want terminal effects better/deeper than most 223 loadings wouldn't it make more sense to go to a larger caliber?
View Quote


Why, when you can get the results that you want from a smaller, lighter, less recoiling platform that you're already using?
Link Posted: 6/5/2003 9:56:04 AM EDT
[#32]
Quoted:
Quoted:
Quoted:
Quoted:

Just curious here, why would you want to shoot 75gr ammo?  Stick w/ 55 or 62, IMHO
View Quote


More accuracy and better terminal performance with the 75gr.
View Quote


OK: 1)You're overspecializing the gun/ammo match to get that accuracy and I'm not convinced accuracy WILL be better than with a 69gr or a 64 gr etc.
View Quote


Actually, accuracy IS better with the proper twist rate.  Ever notice that longe range match shooters use 75/77/80/90 gr bullets?

2) Very few (if any) 75 gr bullets are going to be fmj so you're depending on soft points etc for tissue destruction. There aren't any 75 gr bullets with steel penetrator cores I'm aware of so It's not for penetration. Please see the ammo faq for discussions of 223 wound effect characteristics re: terminal effect in persons.
View Quote


FMJ?  No, you're right.  They're OTM.  They penetrate well, and they fragment nicely.  Take a look at the Ammo Faq again, and look at the 75/77gr gelatin experiment tacked at the top of the ammo forum.

3) If you really want terminal effects better/deeper than most 223 loadings wouldn't it make more sense to go to a larger caliber?
View Quote


Why, when you can get the results that you want from a smaller, lighter, less recoiling platform that you're already using?
View Quote


Actually the ammo faq shows clearly that fragmentation and (very importantly) yaw depend on velocity. At 75 gr velocity will suffer enourmously in a 223 with it's small case, especially from a shorter barrel, and especially at any appreciable distance from the muzzle, accuracy notwithstanding,match shooters are irrelevant to the stated parameters...with different criteria . 75 grain projectiles are impressive wound generators from a 243(which has nearly twice the case capacity) but will degrade significantly from a 223 if for no other reason than the lessened velocity. Read the faq a little closer. No cigar dude but thanks for the input.
Link Posted: 6/5/2003 10:16:45 AM EDT
[#33]
Thats why if you want to pull 75/77gr out ot its maximum performance you gotta use the ones that are loaded very hot, and as far as I know they are not very easy to get. They are also a bit expansive for what you call General purpose / SHTF loading.

But if you have money, they guaranteed deliver more fragmentation at longer ranges. (again, we are talking about hot-loaded ones)
Link Posted: 6/5/2003 10:17:55 AM EDT
[#34]
Quoted:
Read the faq a little closer. No cigar dude but thanks for the input.
View Quote


I don't have to, I helped write a large portion of it.  YOU read it again.  [url=http://www.ammo-oracle.com/#heavier]Q. So are heavier rounds dead for self-defense purposes? [/url]
Link Posted: 6/5/2003 11:02:26 AM EDT
[#35]
One thing to take into account is what length barrel you are using. A 20" barrel will work better with a heavier or longer bullet than a 14.5" or 16" will.
Link Posted: 6/5/2003 11:10:42 AM EDT
[#36]
Quoted:
One thing to take into account is what length barrel you are using. A 20" barrel will work better with a heavier or longer bullet than a 14.5" or 16" will.
View Quote


A 20" will only extend your fragmentation range a bit more if your barrel is 1:7.  With 1:9 you will get better accuraccy with the 20" due to the higher velocity (at least that is something I've noticed).
Link Posted: 6/5/2003 11:21:00 AM EDT
[#37]
Quoted:
OK: 1)You're overspecializing the gun/ammo match to get that accuracy
View Quote

No I'm making the rifle MORE flexible and can shoot everything from 55gr M193 up to the 80gr loads.


I'm not convinced accuracy WILL be better than with a 69gr or a 64 gr etc.
View Quote

Then I suggest a visit to one of your local High-Power matches.


Very few (if any) 75 gr bullets are going to be fmj so you're depending on soft points etc for tissue destruction.
View Quote

Nope - there are no 75gr FMJs or softpoints - I'm talking about using the 75gr Hornady OTMs that are recommended by Dr. Roberts.  I'm relying on bullet fragmentation for tissue destruction.

BTW at $18 for 50 rounds this stuff isn't going to break the bank.


There aren't any 75 gr bullets with steel penetrator cores I'm aware of so It's not for penetration.
View Quote

The steel penetration core was for penetrating the body armor & helments at enemy troops at 600M.  How many citizens do you see needing to lay down fire support against armored troops at 600M?


Please see the ammo faq for discussions of 223 wound effect characteristics re: terminal effect in persons.
View Quote

Hmm I may have a bit or two in there myself.  But I don't have to.  Not only is there Tajana's and Brouhaha's excellent test - the recommendation comes from one of the most respected researchers in the field.  The work was published by the International Wound Ballistics Assoc ("The Wounding Effects of 5.56mm/.223 Law Enforcement General Purpose Shoulder Fired Carbines....", IWBA Journal, Vol 3, No. 4 (1998)).


3) If you really want terminal effects better/deeper than most 223 loadings wouldn't it make more sense to go to a larger caliber?
View Quote

Hmm I can think of several reasons not to:
1) I already have a 5.56mm rifle
2) 5.56 is lighter (you can carry more)
3) Less Recoil
4) Smaller weapon (ever compare a 5.56 rifle to a .308 rifle?)
5) Versatility.  I can use use the less expensive 55gr for plinking or short range (say 50y or less) practice for a near identical flight path.
Link Posted: 6/5/2003 11:32:31 AM EDT
[#38]
On the subject of 75/77 grain bullets, my 1/9 20" AR and 24" handles them just fine with no visible difference in accuracy...to me anyway.

That said, IMHO, 1/9 is the most versatile.  Barrel length plays a factor too.  Don't forget that!

H
Link Posted: 6/5/2003 11:39:16 AM EDT
[#39]
Fragmentation has nothing to do with rate of twist.

75 grain ammo will have improved lethality at ALL ranges than M193.

75 grain Hornady OTM will fragment at FAR FAR lower velocities than M193.  

75 grain ammo will fragment at much further distances than M193.

Loading M193 to NATO pressure will still give inferior terminal performance to 75 grain OTM loaded to SAAMI pressures.

At any realistic urban engagement range you will not be able to tell the difference in NATO loaded or SAAMI loaded 75 grain ammunition.  How many shots do you think you will be taking at 150+ yards?

75 grain ammo is available at [url]www.radomski.us/njhp/major.htm[/url] for $255 and M193 is $199 [url]http://www.ammoman.com/webstore_223.htm[/url] Of course the M193 is new and has staked and sealed primers but the difference in price vs performance is not out of whack.

The 75 grain ammo is more lethal at ALL ranges and its more accurate all ALL ranges.

You can stick with M193 all you want but its still an inferior performer in all aspects of terminal performance.  M855 is even worse and costs more.

M855 was designed to punch through steel helmets at 800 yards not 600 yards.  M855 is a poor penetrator through automobiles, auto galss etc as it breaks up as soon as it hits something hard.

If you want penetration go buy Federal Trophy Bonded Bear Claw 55 grain hunting ammo.  Its the best barrier ammo made for 5.56/.223 rifles.

The Winchester 64 grain Power Point and Power Point Plus bullets have shitty BC and drop off the face of the earth at long range.

Even though the 64 grain PP is a soft point it does not have good barrier penetrating capabilities like the TBBC load.
Link Posted: 6/5/2003 12:06:51 PM EDT
[#40]
Quoted:
Read the faq a little closer. No cigar dude but thanks for the input.
View Quote


That pretty arrogant for a know nothing newbie.  Too bad your wrong on all counts.
Link Posted: 6/5/2003 7:20:07 PM EDT
[#41]
Quoted:
Quoted:
Read the faq a little closer. No cigar dude but thanks for the input.
View Quote


That pretty arrogant for a know nothing newbie.  Too bad your wrong on all counts.
View Quote


Well heck, you're right. That was arrogant of me. I apologise. Somewhere along the line though the topic strayed a little from the original question. It went from the general(which is better?) to the specific (long range match, heavy bullet only, grunt!). In context of the original question, and in context of all around usage I stand by my comments. I do however respect other opinions even if It sounds otherwise. As for "newbie", I'm damn near 50 and have been shooting since age 10. The two most overused words on the internet are "teen", and "newbie" People use "newbie" as an alpha male/playground bully slam when they feel threatened, pissed off, or insecure. The only place you see such behavior is on the internet because face to face it would prove too costly to say on a day to day basis both in terms of hide(you know, skin) and employment.  As for the comment "know nothing", I bet I know stuff you don't know, nyah, nyah, nyah. An AR is like anything else in this day and age. Eventually someone will take it to a ridiculous extreme or argue that the extreme is the norm. 99% of the uses anyone here has for an AR is served very well by a 1/9 and bullets no heavier than 69 gr. Anything heavier is a SPECIALTY round and should be delegated to the proper firearm as such.
Link Posted: 6/5/2003 11:21:49 PM EDT
[#42]
Quoted:
Quoted:
OK: 1)You're overspecializing the gun/ammo match to get that accuracy
View Quote

No I'm making the rifle MORE flexible and can shoot everything from 55gr M193 up to the 80gr loads.
You need an 80 gr load?


I'm not convinced accuracy WILL be better than with a 69gr or a 64 gr etc.
View Quote

Then I suggest a visit to one of your local High-Power matches.
As I have said elswhere...a specialty. Not really part of the original posit.

Very few (if any) 75 gr bullets are going to be fmj so you're depending on soft points etc for tissue destruction.
View Quote

Nope - there are no 75gr FMJs or softpoints - I'm talking about using the 75gr Hornady OTMs that are recommended by Dr. Roberts.  I'm relying on bullet fragmentation for tissue destruction.
Not enough velocity.
BTW at $18 for 50 rounds this stuff isn't going to break the bank.
Cool.

There aren't any 75 gr bullets with steel penetrator cores I'm aware of so It's not for penetration.
View Quote

The steel penetration core was for penetrating the body armor & helments at enemy troops at 600M.  How many citizens do you see needing to lay down fire support against armored troops at 600M?
Always look ahead :o)

Please see the ammo faq for discussions of 223 wound effect characteristics re: terminal effect in persons.
View Quote

Hmm I may have a bit or two in there myself.  But I don't have to.  Not only is there Tajana's and Brouhaha's excellent test - the recommendation comes from one of the most respected researchers in the field.  The work was published by the International Wound Ballistics Assoc ("The Wounding Effects of 5.56mm/.223 Law Enforcement General Purpose Shoulder Fired Carbines....", IWBA Journal, Vol 3, No. 4 (1998)).
Smoke and mirrors....everything you read etc.

3) If you really want terminal effects better/deeper than most 223 loadings wouldn't it make more sense to go to a larger caliber?
View Quote

Hmm I can think of several reasons not to:
1) I already have a 5.56mm rifle
2) 5.56 is lighter (you can carry more)
3) Less Recoil
4) Smaller weapon (ever compare a 5.56 rifle to a .308 rifle?)
5) Versatility.  I can use use the less expensive 55gr for plinking or short range (say 50y or less) practice for a near identical flight path.
View Quote


I thought everyone here had more than 1 weapon and planned on buying more?
Recoil is a factor with you? Never been a prob with me. It's not like were doing full auto with 458 win mags now is it?
Link Posted: 6/6/2003 3:21:05 AM EDT
[#43]
I have a RRA M4.  16 in. M4 Wilson Barrel 1 in 9.  A while back I was seeking out which ammo to use for duty use, primarily cqb.  I observed to much him-haw about the heavy loads out of my type of barrel.  So I found a happy medium and went with the 60 gr. TAP ammo from Hornady.  Too much speculation on heavy rounds to both ends of the spectrum. ie will work/will not work.  Needed something I new would work....so I went with the 60 gr. TAP.  Good terminal balistics, etc.
Just my little two cents.
Link Posted: 6/6/2003 5:35:45 AM EDT
[#44]
Quoted:


I'm not convinced accuracy WILL be better than with a 69gr or a 64 gr etc.
View Quote

Then I suggest a visit to one of your local High-Power matches.
As I have said elswhere...a specialty. Not really part of the original posit.
View Quote

View Quote

Its ENTIRELY part of the orginal post and a direct answer to YOUR point.

The post is about which twist is better 1:7 or 1:9.  The 1:7 twist has been shown it can operater a WIDER range of bullets.  Including the more accurate heavy match rounds.

You doubted the statement and I responed pointing you to a local place where you could find the proof.



Nope - there are no 75gr FMJs or softpoints - I'm talking about using the 75gr Hornady OTMs that are recommended by Dr. Roberts.  I'm relying on bullet fragmentation for tissue destruction.
View Quote

Not enough velocity.
View Quote

Really? and how do you back your statement up?  DevL was right you are a newbie and don't know WTF you are talking about.  


Smoke and mirrors....everything you read etc.

Would sombody please show this Troll to the door?  Anybody who dismisses valid peer reviewed scientific research as 'smoke and mirrors' - especially when offering zero evidence is just trying to stir up trouble.


I thought everyone here had more than 1 weapon and planned on buying more?
View Quote

And how is that relavant?  I only have 2 hands and can only carry 1 rifle at a time.


Recoil is a factor with you? Never been a prob with me.
View Quote

Recoil is a factor with EVERYONE.  Recoil will determine how fast you can place a 2nd shot (follow up or another target).

I don't care how quick you are with a .308 - you will be faster with a .223.
Link Posted: 6/6/2003 5:55:31 AM EDT
[#45]
Quoted:
As for "newbie", I'm damn near 50 and have been shooting since age 10.
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Irrelevant since you obviously aren't up on 5.56 ballistics (flight or terminal) - and this topic (Best Twist) is indirectly a discussion on both.


I bet I know stuff you don't know,
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I don't doubt that.  But on stuff you obviously are not informed about perhaps you should read more and leave the snide comments out of the thread.


99% of the uses anyone here has for an AR is served very well by a 1/9 and bullets no heavier than 69 gr.
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90% of AR shooters probably only shoot .223 - so why do you need a 1:9 twist or even a Military chamber for 5.56?

WHY LIMIT YOURSELF?

A 1:9 is a big step up from the 1:12 because it allows you to shoot a wider variety of ammo.   BTW the 68 & 69gr rounds are MATCH/SPECIALTY rounds - as are the 73,75, 77, 80 rounds - the heavier rounds just DO IT BETTER.  Again why limit yourself to above average rounds (the 68/69) when you can get the etraordinary rounds?

Going to 1:7 allows everything the 1:9 does but gives the shooter the OPTION of going heavier if they choose.  The only thing they loose is marginally less barrel life - but heck you do that when going from a 1:12 to a 1:9 anyway.

Anything heavier is a SPECIALTY round and should be delegated to the proper firearm as such
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My rifles are General Purpose Tools for my shooting needs.  I select the appropriate ammo for the job.
Link Posted: 6/6/2003 6:21:05 AM EDT
[#46]
Quoted:

Going to 1:7 allows everything the 1:9 does but gives the shooter the OPTION of going heavier if they choose.  The only thing they loose is marginally less barrel life - but heck you do that when going from a 1:12 to a 1:9 anyway.

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Disagree.  The accuracy sweet spot for 1:7 twist is 69grn and for 1:9 twist 62 grn (1:12 55grn). Yes, of course you can shoot other bullet weights but with marginal loss of accuracy.
Link Posted: 6/6/2003 6:50:00 AM EDT
[#47]
Quoted:
Quoted:

Going to 1:7 allows everything the 1:9 does but gives the shooter the OPTION of going heavier if they choose.  The only thing they loose is marginally less barrel life - but heck you do that when going from a 1:12 to a 1:9 anyway.

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Disagree.  [red]The accuracy sweet spot for 1:7 twist is 69grn and for 1:9 twist 62 grn (1:12 55grn).[/red] Yes, of course you can shoot other bullet weights but with marginal loss of accuracy.
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Is this from personal experience, documentation, rumor, ...?
Link Posted: 6/6/2003 8:38:41 AM EDT
[#48]
Quoted:
Quoted:
Quoted:

Going to 1:7 allows everything the 1:9 does but gives the shooter the OPTION of going heavier if they choose.  The only thing they loose is marginally less barrel life - but heck you do that when going from a 1:12 to a 1:9 anyway.

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Disagree.  [red]The accuracy sweet spot for 1:7 twist is 69grn and for 1:9 twist 62 grn (1:12 55grn).[/red] Yes, of course you can shoot other bullet weights but with marginal loss of accuracy.
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Is this from personal experience, documentation, rumor, ...?
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Jetlag, when dealing in rumor I try and state so.  I'm posting from personal experience and believe you can obtain the same information from most manufacturers of AR's as well as barrel manufacturers.  (At my age, some things I've known too long to remember the source - when I first walked and talked, where I first read that George Washington was our first president and and barrel twist rates and the corresponding bullet weights are just four !!)

Let's leave the world of shooting for just a moment and look at the world of practical business.  No way would ArmaLite, Bushmaster, Colt, DPMS, Olypmic, RRA, etc., spend millions of dollars to inventory varying barrel twists if they could simply use a 1:7 twist and shoot all bullet weights.  Now the above manufacturers, and virtually all other manufacturers of AR's do stock, offer and sell barrels with varying twist rates and they're doing so in order to give their customer the choices needed for various types of shooting.  For 'most' of us a 1:9 barrel offers max versatility and I would venture to say most AR's sold to the civilian market have 1:9 barrels.  However, the military and many distance shooters will opt for 1:7 as that allows them to shoot heavier bullets with accuracy (and better penetration).  

(One of these days I'm going to have to re-barrel one of my old AR-18's or AR-180's.  Being traditional, I'm going to go right back to 1:12 twist as that's what these old guns had and keep shooting 55grn Mil-Surp.)

[b]Might there be some quibbling about being as precise as I've been in posting the twists and bullet weights - yes.  However, as a general statement I stand by the information above.[/b]
Link Posted: 6/6/2003 9:42:02 AM EDT
[#49]
I just thought you were goin a little light there. I guess you could ask every shooter on the line what the best bullet for a twist is and get a different answer every time. I agree that you're best served with a twist that "fits" your choice of ammo.
Link Posted: 6/6/2003 10:04:33 AM EDT
[#50]
Quoted:

I agree that you're best served with a twist that "fits" your choice of ammo.

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And that's all I was trying to say in that long-winded post above - match your bullet weight to your barrel twist.

(I'll bet you dollars to doughnuts that "Forest" was typing at the speed of light when he made his post.  I know him and the Maryland Group to be a very knowledgeable crowd.)
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