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Posted: 11/24/2003 9:07:35 PM EDT
The whole 75/77 gr heavyweight bullet interest got me wondering what is the heaviest weight bullet a 1:9 can stabilize?  I know, I already looked at the ammo oracle and it was kind of vague on this questions.  My impression is once you pass the 70 gr weight it starts to get iffy.  If anyone has specific brands/loads they know work or don't work in this range I would appreciate it.  

Gotta find a poor man's version of the heavyweight rounds for us 1:9 owner's, ya know?
Link Posted: 11/24/2003 11:29:18 PM EDT
[#1]
Link Posted: 11/25/2003 4:45:19 AM EDT
[#2]
Hey all, is there any way to tell the twist on a bbl that is not marked?
 I'm thinking its a 1/9 but would like to know for sure if possible.
Link Posted: 11/25/2003 5:24:19 AM EDT
[#3]
Quoted:
72gr is about the heaviest (i.e., longest) bullet that will always be stabile in a 1:9.  Note that most barrels are not exactly 1:9.  Some may be closer to 1:8.5, and others closer to 1:9.5, so what is true for one rifle isn't necessarily true for another that looks just like it.

Also, the load you use and the environmental conditions (temp, humidity, altitude, etc.) all play a part.

-Troy
View Quote


Hadn't even thought about the slightly different twist.  I knew environmental conditions will play a factor.  So what you are trying to say is 72 gr a good starting point and just start trying ammo in my rifles.  Gotcha.



Link Posted: 11/25/2003 5:25:33 AM EDT
[#4]
Quoted:
Hey all, is there any way to tell the twist on a bbl that is not marked?
 I'm thinking its a 1/9 but would like to know for sure if possible.
View Quote


There's a way to do everything!  Take a cleaning rod and put a patch on the end, preferably one that will give you a tight fit.  Put the rod in until you feel resistance, where the patch engages the rifling.  Put a mark on the top of the cleaning rod, and push in.  It should rotate with the rifling.  When the mark comes to the top again, measure how far the rod has gone in.  If one revolution took 7", it's a 1-7.  If it took 9", it's 1-9.  

As Dawg said, it's iffy once you get into the 70's.  I've shot 77's that stabilized and 75's that didn't, it depends on the bullet design and the load.
Link Posted: 11/25/2003 5:29:34 AM EDT
[#5]
Quoted:
Quoted:
Hey all, is there any way to tell the twist on a bbl that is not marked?
 I'm thinking its a 1/9 but would like to know for sure if possible.
View Quote


There's a way to do everything!  Take a cleaning rod and put a patch on the end, preferably one that will give you a tight fit.  Put the rod in until you feel resistance, where the patch engages the rifling.  Put a mark on the top of the cleaning rod, and push in.  It should rotate with the rifling.  When the mark comes to the top again, measure how far the rod has gone in.  If one revolution took 7", it's a 1-7.  If it took 9", it's 1-9.  

As Dawg said, it's iffy once you get into the 70's.  I've shot 77's that stabilized and 75's that didn't, it depends on the bullet design and the load.
View Quote

Thanks much!  I'll give it a try next cleaning.
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