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Posted: 3/22/2006 2:17:32 PM EDT
What ammo do you recomend for a new chrome lined 1-9 barrel.  Im still kinda confused on the whole twist in relation to ammo.  Lets see if i get this right; 1-7 is good for heavier, and 1-9 for lighter?  So what is lighter, higher grain number or lower?
Link Posted: 3/22/2006 2:27:32 PM EDT
[#1]
The 7 twist barrels are generally good for 75 and 77 grain bullets fed from the magazine. The 9 twist barrels are generally good for 68 and 69 grain bullets fed from the magazine.

However, there are many 9 twist barrels that will shoot the heavier 75 and 77 grain bullets quite well. And there are some 7 twist barrels that will shoot the 68 and 69 bullets better than the 75 and 77's.

Your best bet is to get a box of each bullet weight and go shoot them in your gun. This will tell you what works best for you.

Charles the Gunsmith.  
Link Posted: 3/22/2006 3:50:53 PM EDT
[#2]
I would think chamber dimensions and load recipe play as much a part.

If you shoot a 55 grain really hot through a 1/7, you could overstablize or actually start  to rip the jacketing off the bullet.

It's kind of like the speed / feed relationship on a lathe. You can feed a 55 grain bullet down the 1/7, but the velocity has to be within a range or you have bad days.  

I've tried shooting 77 grain through 1/9 barrels and at medium ranges (600 - 1000) yards it doesn't work. At least it doesn't work for me.

I would stick with 40 - 62 grains for a 1/9, to get the most potential. Certainly though, you can try the heavier loads to see the performance for your individual weapon.

Link Posted: 3/22/2006 4:15:04 PM EDT
[#3]

Quoted:
I would think chamber dimensions and load recipe play as much a part.

If you shoot a 55 grain really hot through a 1/7, you could overstablize or actually start  to rip the jacketing off the bullet.

It's kind of like the speed / feed relationship on a lathe. You can feed a 55 grain bullet down the 1/7, but the velocity has to be within a range or you have bad days.  

I've tried shooting 77 grain through 1/9 barrels and at medium ranges (600 - 1000) yards it doesn't work. At least it doesn't work for me.

I would stick with 40 - 62 grains for a 1/9, to get the most potential. Certainly though, you can try the heavier loads to see the performance for your individual weapon.




I've never heard of anyone having trouble with a 55 grain bullet in a 1/7 BBL that stayed within the accepted norm for pressures or velocity. Heck, 5.56 is faster then sammi allows for civi .223 anyways. Maybe with a 40-45 grain you MIGHT have problems, but my 1/7 rifle would shoot those all day long with no problem at all.
Link Posted: 3/22/2006 4:35:19 PM EDT
[#4]
I wish had these problems. The ONLY thing I can get here is 55grain winchester, or 55 grain wolf.
Link Posted: 3/22/2006 8:45:51 PM EDT
[#5]
I think i am going to just bring a few boxes of 60 - 70 range and see what I like, its a brand new gun so im sure i have allot to do to get it accurate.
Link Posted: 3/22/2006 8:57:11 PM EDT
[#6]
55-62gr plinking ammo
Link Posted: 3/22/2006 9:45:25 PM EDT
[#7]

Quoted:
The 7 twist barrels are generally good for 75 and 77 grain bullets fed from the magazine. The 9 twist barrels are generally good for 68 and 69 grain bullets fed from the magazine.

However, there are many 9 twist barrels that will shoot the heavier 75 and 77 grain bullets quite well. And there are some 7 twist barrels that will shoot the 68 and 69 bullets better than the 75 and 77's.

Your best bet is to get a box of each bullet weight and go shoot them in your gun. This will tell you what works best for you.

Charles the Gunsmith.  


What he said ^^^^^^^^^^^^^^^^^^^^^
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