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 What are suitable bullet weights for 5.56 in a 1:8 barrel.
THUNDERKISS  [Member]
2/11/2007 12:08:22 AM
Just bought a Tikka T3 rifle calibered in 5.56x45 with a barrel that has 1:8 rifling. I know that its not an AR, but I figured that this would be the best forum to post in to obtain the best information regarding appropriate bullet weights for this rate of twist 'cause there are so many AR's and shooters that use 5.56x45 cartridge.

So, what is the range of bullet weights most suitable for use in a barrel with 1:8 rifling?

Thanks all,

TK
ZeroedIn  [Member]
2/11/2007 12:23:11 AM
55 grains and up
Frag  [Member]
2/11/2007 12:50:50 AM

Originally Posted By THUNDERKISS:
Just bought a Tikka T3 rifle calibered in 5.56x45 with a barrel that has 1:8 rifling. I know that its not an AR, but I figured that this would be the best forum to post in to obtain the best information regarding appropriate bullet weights for this rate of twist 'cause there are so many AR's and shooters that use 5.56x45 cartridge.

So, what is the range of bullet weights most suitable for use in a barrel with 1:8 rifling?

Thanks all,

TK

I personaly like the 1 in 8" twist barrels.

Have a look at the Ammo-Oracle, in perticular the Barrel Twist Section it goes into detail and will help you get better educated with the whole Barrel Twist issue
dynemd  [Member]
2/11/2007 1:13:09 AM
That's a good Ammo Oracle article. I'd say weights between 77 and 55 grains should do well.
Frag  [Member]
2/11/2007 2:03:38 AM

Originally Posted By dynemd:
That's a good Ammo Oracle article. I'd say weights between 77 and 55 grains should do well.

One thing to remember, try not to get too close to the edge of the capability envelope. You want to stay as close to the middle as possible (with a lean to the heavy side, imho).
FALARAK  [Team Member]
2/11/2007 2:10:34 AM

Originally Posted By ZeroedIn:
55 grains and up


Why 55?

The correct answer from my testing is 45gr and up. People have reported shooting the Nosler 40gr bullets without them vaprizing as well, but I havent.

I have shot hundreds of the the 45gr Winchester loads in a 1:8 20" barrel, and they averaged .5 to .9MOA depending on the day.


You can shoot pretty much any commercially available factory load in .223 or 5.56 in a 1:8 barrel.
ZeroedIn  [Member]
2/11/2007 2:44:57 AM

Originally Posted By FALARAK:

Originally Posted By ZeroedIn:
55 grains and up


Why 55?

The correct answer from my testing is 45gr and up. People have reported shooting the Nosler 40gr bullets without them vaprizing as well, but I havent.

I have shot hundreds of the the 45gr Winchester loads in a 1:8 20" barrel, and they averaged .5 to .9MOA depending on the day.


You can shoot pretty much any commercially available factory load in .223 or 5.56 in a 1:8 barrel.


Playing it safe, like how some 1/9 barrels will stabalize 75 gr and some wont due to the fact that they may not be exactly 1/9 (variance from 1/9.5 to 1/8.5). I was thinking that with a slightly-faster-than-true 1/8 twist, bolt action, and extra 2.5 inches of barrel, that the tiny loads would have a potential to suffer.

I tried out the 75 gr in my 1/9, and accuracy was OK: better than M193, not as good as the 68/69 gr OTMs. What did I stand to lose with understabalization? 17 bucks on a box of ammo. What did I stand to gain? A considerable improvement in terminal wounding effects. With the varmint rounds, you stand to lose as much money with overstabalization but the only gain is, well, a varmint round. I guess I'm just speaking out of a combination of my stinginess, caution, and my bias against the sub-55 gr bullets.

I could be wrong
THUNDERKISS  [Member]
2/11/2007 4:00:42 PM
Guys,

Thanks for all the replies and help.

Based upon your suggestions, I'll think that I'll get a box of several different bullet weights from 55 on up to the heavier 75-77 grain offerings and see what flavor my rifle likes the best. I think that it is wise to stay clear of anything lighter than 55 grains due to the fact that they may tend to disintegrate due to their more fragile construction. Already have 1k rounds of Federal American Eagle 55 gr. FMJBT and will give them a try when the weather permits. I am not worried about a little overstabilization in this particular weight and think/hope that they will probably do fine.


Thanks again for the advice and general guidelines since I now have an idea as to what I need to do.

All the best,

TK
Frag  [Member]
2/11/2007 4:27:38 PM

Originally Posted By THUNDERKISS:
Guys,

Thanks for all the replies and help.

Based upon your suggestions, I'll think that I'll get a box of several different bullet weights from 55 on up to the heavier 75-77 grain offerings and see what flavor my rifle likes the best. I think that it is wise to stay clear of anything lighter than 55 grains due to the fact that they may tend to disintegrate due to their more fragile construction. Already have 1k rounds of Federal American Eagle 55 gr. FMJBT and will give them a try when the weather permits. I am not worried about a little overstabilization in this particular weight and think/hope that they will probably do fine.


Thanks again for the advice and general guidelines since I now have an idea as to what I need to do.

All the best,

TK

American Eagle 55gr FMJ-BT is a great round, was my favorite by far for plinking untill the price went up. It's nice clean quality LC brass (most of the time) with a 55 grain thin jacket over lead core bullet and was very accurate in my 16" 1 in 9" twist barrel. Beautiful ammo!

The AE223 55gr FMJ-BT is very similar to the M193. Here is a quote from Ammo-Oracle:

Q. OK, that's complex. Simple question: Can I fire M193 ammo in my 1:7 or 1:9 twist barrel?

Yes.

M193 is essentially a "universal" round; able to be stabilized by barrels with twists between 1:14 and 1:7. Point of impact will change slightly compared to an M855 zero, so rezeroing is recommended.

paulosantos  [Team Member]
2/11/2007 7:04:29 PM
The 1x8 twist is truly the All-Purpose Twist.
THUNDERKISS  [Member]
2/11/2007 9:09:35 PM

Originally Posted By paulosantos:
The 1x8 twist is truly the All-Purpose Twist.


That's nice to know.

Frag,

I really liked that link to ammo-oracle. It educated me pretty quickly as to what I wanted in ammunition for the Tikka T3. Seeing as it is the cheapest and most commonly available ammo out there, I'll probably be sticking with M193 type ammo of whatever brand that I can find unless it is a lousy performer in the Tikka.


Thanks guys.

TK
FALARAK  [Team Member]
2/11/2007 10:50:59 PM

Originally Posted By paulosantos:
The 1x8 twist is truly the All-Purpose Twist.


I hate to generalize.... but I personally agree with this statement. I wish everything came in this twist.
Frag  [Member]
2/12/2007 6:27:35 AM

Originally Posted By THUNDERKISS:

Originally Posted By paulosantos:
The 1x8 twist is truly the All-Purpose Twist.


That's nice to know.

Frag,

I really liked that link to ammo-oracle. It educated me pretty quickly as to what I wanted in ammunition for the Tikka T3. Seeing as it is the cheapest and most commonly available ammo out there, I'll probably be sticking with M193 type ammo of whatever brand that I can find unless it is a lousy performer in the Tikka.


Thanks guys.

TK

Glad I could help