58-115 grain RBT slugs to try out from something interesting.

[JamesD.]

72's are .614" OAL .2573" not lubed yet but I see that I probably will from fast leading up. 1095fps. 32" 0.880" Lilja Bull 1:10



72's from the 26" 1:14 are being spat out at 995. 




I'm hoping & praying I get even 1/2 as good as John Bowman did. 1/8" moa all day 19/20 through 1" Ram @ 300yrds. He used 257420 cast. 
https://www.pyramydair.com/blog/2012/03/lasso-2012/



If I get 1/4" moa all day tethered at a harmonic pressure everything likes, I'll be thrilled. I'm okay with going down in power and utilizing anything line 40-68. 
Don't doubt that. I've seen what a .31.9 .25 at 940 could do at 300+ so this .257 should kick the ever loving poop out of a 31.9 grain slug. 
I'm getting .212 bc What do any of you get with everything from .257 to the 6mm, .270, etc?

Two .257 Scandalous rifles from Santa. 

 

[Flintsack]

NICE!

mike

 

[Loren]

Really nice rifles! I'm looking forward to hearing how your 1:10 barrel does. Really nice rifles!

 

[woogie_man]

Ok now those are some cool rifles!



Make sure to get some video of you shooting them.

 

[Scotchmo]

…

72's from the 26" 1:14 are being spat out at 995. 


I'm hoping & praying I get even 1/2 as good as John Bowman did. 1/8" moa all day …

…He used 257420 cast. 
…

If I get 1/4" moa all …


I'm getting .212 bc What do any of you get with everything from .257 to the 6mm, .270, etc?
…

My favorite is the Arsenal 257420 BT. 71.5gr currently at 990fps gives me .160 BC at sea level (.170 at 2000ft). 1:14 twist TJ, 36” long. I based my selection on the success of those (Bowman and others) .257 airgunners.

Second best shooting in this barrel is the Arsenal 257388, 87gr. .210 BC at 2000ft elevation.

You mean 1/8 moa and 1/4 moa, as it’s an anglular measurement, not an inch measurement.

 

[RM.510bigbore]

 These are my .510 650 grain spire point boat tail. They are 1.375 inchs long. I have only shot to 300 yards but a b.c of .5 is getting me on target. For comparison is a .510 475 grain massive hollow point has a b.c of .250. They both shoot well outta my Texan. Noe and accurate molds. You should give powder coating your slugs a try. 750 fps with 650 grain in stock Texan tx2 valve. I saw some accurate molds for a 7mm 190 grain boat tail that might be a start for a long ranger air gun The limit is length accurate molds maximum length is 1.375 inch long for.cast bullets length. I think the lee design .308 230 grain spire PT boat tail is a b.c of .6 something. So for now a lee .308 230 grain is the ballistic king for cast ammo in airguns.

 

[JamesD.]

I'm loving the Griffin 58-88 4S RBT HP's.



Thanks guys and I'll try to get groups on paper in hundred yard intervals.

Scotchmo: I was saying John's shot 1/8"moa consistently. As in hole in hole repeatedly. So 1/2 as good is 1/4" c-t-c at 100. I don't know where they'll fall apart weight/length, distances from 1:14 & 1:10

I might try a 1:7 for 88-115 6S

 

[Scotchmo]

I'm loving the Griffin 58-88 4S RBT HP's.



Thanks guys and I'll try to get groups on paper in hundred yard intervals.

Scotchmo: I was saying John's shot 1/8"moa consistently. As in hole in hole repeatedly. So 1/2 as good is 1/4" c-t-c at 100. I don't know where they'll fall apart weight/length, distances from 1:14 & 1:10

I might try a 1:7 for 88-115 6S

I think my 87gr 257388 slugs are a little too long/heavy for optimal performance in the 1:14 barrel. They might do better in your 1:10 barrel. I don’t think a 1:7 is going to be all that useful as it’s only needed for much longer/heavier slugs, and it’s very difficult to get adequate velocity from a .257 airgun with 100gr+ slugs. I’m assuming that you want the heavier slugs for their better BC and long range capability.