Who has shot 55gr ammo through there 1in7" Twist Swiss Arms

S

Steve Janes

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I have a Black Special with a 1in10" Twist and have had great accuracy with 55gr ammo. I have just agreed to a deal to purchase a 1in7" Twist Classic Green.

Usually, I shoot mostly 55gr ammo. It would be nice to occasionally shoot something heavier but chances are, it won't happen. I am a high volume shooter, last year I fired about 5000 rounds of 55gr ammo through my Black special, so if 55gr through a 1-7" will decrease barrel life, I wanna know about it. Accuracy is important to me. I want to be shooting as accurately as possible.

With these parameters in mind, how will the 55gr perform in a 1in7" Twist barrel? Will there be destabilization at colder temps? I'm looking for experience from people who have shot 55gr ammo through there 1in7" Twist Swiss Arms

Thanks

Steve
 
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I've shot lots of 55 grain and also lots of 62 grain bulk ammo through 1 in 7 twist SAN barrels. I don't notice any difference in accuracy. The most accurate combo I've found is 63 grain RUAG ammo through a 1 in 10 twist barrel.

I've actually never understood why the 1 in 7 twist models seem to be more desirable. For the run-of-the-mill ammo that one would normally shoot from these guns it seems to make little difference. Moreover, the 1 in 10 barrels are optimized for the 63 grain RUAG ammo.

I suppose if you wanted to play around with much heavier weight bullets, the the 1 in 7 might make a difference. But, I've never tried anything heavier than 63 grain.
 
I have shot every flavor through my 1/7 Classic Green from 45-77 grain ammo. I really haven't noticed any huge gains in accuarcy among them. I rarely shoot beyond 100 yards though. I would prefer a 1/9 twist though.
 
1:7 is a do-all calibre. It's not fine tuned, but it's good enough that shooter error usually negates any obvious differences.

The main aspect of the faster twist is that the bullet has to travel farther in a 1:7 twist barrel to be stabilizes in flight than it would in a 1:10 twist barrel. So, it's that wonky first section of the flight path that opens up groupings. That said, the quality of the bullet will have a greater impact on how fast the bullet stabilizes than the first few wonky micro seconds of the flight.
 
As long as it will group well (with 55gr), and there are no destabilization issues (with 55gr), then it's good to go!!!

Thanks everyone, that about answer's what I was asking.

Steve
 
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440 meter shooting in -10c weather, 55gr FMJ American Eagle. Groupings were well within 10" on the torso of my ODPL full size steel gong.

No pics of the target grouping, but PM Vviking if you question the accuracy of the story.

Here is the target prior to to give you a sense of scale.

DSC01299-1.jpg
 
Kevin M. said:
440 meter shooting in -10c weather, 55gr FMJ American Eagle. Groupings were well within 10" on the torso of my ODPL full size steel gong.

No pics of the target grouping, but PM Vviking if you question the accuracy of the story.
Click to expand...

I believe you just fine, my Swiss loves that stuff!!

I shot that same ammo this afternoon at 500yds (460m) using only a 3.5X Acog off the mag at a Fig 12.
First target: 10 for 10, 2nd target: 14 out of 15 Center mass and in the head (one went high and just over the target):D

AE is great stuff!!

I initially measured them wrong, here's the fix:

10 round group.
8 rounds under 10"
The 9th and 10th kicks it out to 13.5".

15 round group.
12 rounds under 10"
The 13th opens it up to 11"
14th opens group up to 15.5" Sh!tty!!
The 15th round is awol.

All 24 rounds landed within a 16" circle.
 
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Kevin M, J996, are your Swiss Rifles 1-7" Twists.

I actually thought to PM you (J996) before I made the thread as I know you do lots of this stuff. However I was pretty sure your Swiss was a 1-10" twist. Was i wrong???
 
I did noticed in 2 of my 3 MR-1, 1 in 9 twist, ( the third one still unfired) the 55 gr slug dont provide me with tight group as it will do with 45-52-69-75-77gr bullet, maybe a coincidence, never had much success with those bulk FMJ 55 grainers... JP.
 
caramel said:
I did noticed in 2 of my 3 MR-1 ( the third one still unfired) the 55 gr slug dont provide me with tight group as it will do with 45-52-69-75-77gr bullet, maybe a coincidence, never had much success with those bulk FMJ 55 grainers... JP.
Click to expand...

No offense, but I'm asking people about personnel experience with Swiss Arms rifles with 1-7" Twist Barrels.

While in your past threads, it has certainly appeared as if you have found an ammunition for your MR1's that provides excellent and surprising accuracy that these hands certainly are not capable of reproducing, for now, I would like to stick to people with experience on the same type of rifle I am using.

Thank you

Again, no offense by this.
 
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Steve Janes said:
Kevin M, J996, are your Swiss Rifles 1-7" Twists.

I actually thought to PM you (J996) before I made the thread as I know you do lots of this stuff. However I was pretty sure your Swiss was a 1-10" twist. Was i wrong???
Click to expand...

I believe mine to be a 1 in 10 twist.
In my opinion you should have no problems at all. 1 in 7 has been proven to shoot 55's accurately and I have shot that far with AR15's using 55 grain M193 before.

I will put up some pics in a new tread.

Done:D
http://www.canadiangunnutz.com/forum/showthread.php?t=758004
 
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