Projectile RPM limits...
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Re: Projectile RPM limits...
I refer to the New Years resolution thread.
Re: Projectile RPM limits...
C'mon Con, join the ranks of the 5.6x57 brigade
You know you want to
You know you want to
Re: Projectile RPM limits...
Guys,
I know SMK 6mm 107 gr will blow up at 320 000 rpm, nearly blew old Trev up with one at the range while he was in the butts. Not a scratch on the paper, but a big grey mist at about 980 yds. Also blew some up at about 50 yards. I used to have a 100 yd target with a perfect little comet trail off the side of the hole from one too. So I have ditched the 8 twist for the faster cartridges and gone to 9 twist to get back under the 300 000 mark.
Jeff
I know SMK 6mm 107 gr will blow up at 320 000 rpm, nearly blew old Trev up with one at the range while he was in the butts. Not a scratch on the paper, but a big grey mist at about 980 yds. Also blew some up at about 50 yards. I used to have a 100 yd target with a perfect little comet trail off the side of the hole from one too. So I have ditched the 8 twist for the faster cartridges and gone to 9 twist to get back under the 300 000 mark.
Jeff
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Re: Projectile RPM limits...
Con I have had 2 fast twist 22 cal barrels on a Sako trg 22 that I did with the intention of shooting 75 vmax,s
They shot well at around 3200 out of a 22250 ackley , by no means bench rest accurate ether, but plenty good enough for varmints ,3350 would see 1/10 come apart after about 20-30 rounds on a clean barrel , however I did a 12 twist on my Barnard with the intention of shooting 53 vmax,s
Bc 290 and at 4150 -4250 they are benchrest accurate to 550 yds and very deadly in anything up to reasonable conditions
But I have the urge to try some 80 grain vmax,s so a few weeks back I ordered an 8 twist flutted light varmint maddco
Will be chambered in my all time favourite 220 ackley
Yes I no they may not hold together at the available velocity but it’s time again to give it another go
On a side note nothing in 22 cal kills like a 75 vmax either
They shot well at around 3200 out of a 22250 ackley , by no means bench rest accurate ether, but plenty good enough for varmints ,3350 would see 1/10 come apart after about 20-30 rounds on a clean barrel , however I did a 12 twist on my Barnard with the intention of shooting 53 vmax,s
Bc 290 and at 4150 -4250 they are benchrest accurate to 550 yds and very deadly in anything up to reasonable conditions
But I have the urge to try some 80 grain vmax,s so a few weeks back I ordered an 8 twist flutted light varmint maddco
Will be chambered in my all time favourite 220 ackley
Yes I no they may not hold together at the available velocity but it’s time again to give it another go
On a side note nothing in 22 cal kills like a 75 vmax either
- trevort
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Re: Projectile RPM limits...
frl0173 wrote:I have a video and still shot of a friend shooting his 20-250AI shooting 55gn projectiles and watching them turn to grey mist cloud at about the 20m mark.
This is the saddest post I have ever read
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- trevort
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Re: Projectile RPM limits...
mistit wrote:Con I have had 2 fast twist 22 cal barrels on a Sako trg 22 that I did with the intention of shooting 75 vmax,s
They shot well at around 3200 out of a 22250 ackley , by no means bench rest accurate ether, but plenty good enough for varmints ,3350 would see 1/10 come apart after about 20-30 rounds on a clean barrel , however I did a 12 twist on my Barnard with the intention of shooting 53 vmax,s
Bc 290 and at 4150 -4250 they are benchrest accurate to 550 yds and very deadly in anything up to reasonable conditions
But I have the urge to try some 80 grain vmax,s so a few weeks back I ordered an 8 twist flutted light varmint maddco
Will be chambered in my all time favourite 220 ackley
Yes I no they may not hold together at the available velocity but it’s time again to give it another go
On a side note nothing in 22 cal kills like a 75 vmax either
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Re: Projectile RPM limits...
Mistit,
Maddco still looking at March for 1:8" barrels?
Cheers...
Con
Maddco still looking at March for 1:8" barrels?
Cheers...
Con
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Re: Projectile RPM limits...
Don't cry mate, at least he figured out why the Bergers were vaporizing, exceeding the max recommended velocity according to Berger.
- trevort
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Re: Projectile RPM limits...
I’ve got them going at 3880. Where does Berger say to stop?frl0173 wrote:Don't cry mate, at least he figured out why the Bergers were vaporizing, exceeding the max recommended velocity according to Berger.
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- dashooter
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Re: Projectile RPM limits...
Should be able to get to 4200 fps and still hit rabbits at range Trev based on testing done in September. That’s out of a 1:9 twist barrel.
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Re: Projectile RPM limits...
For those that may pick up on it
It is meant to say amax not vmax in my previous post
It is meant to say amax not vmax in my previous post
- trevort
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Re: Projectile RPM limits...
You talking at about 55 gn 20 cal pills?dashooter wrote:Should be able to get to 4200 fps and still hit rabbits at range Trev based on testing done in September. That’s out of a 1:9 twist barrel.
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