.25 cal 131g .330G7 bullet from Blackjack Bullets for you to drool on ...

[MudRunner2005]

Fastest twist proof makes for .257 is 1&10. They need a minimum order of 10 barrels to make an 7 or 8 twist. I'm working with evolved ballistics right now, they are the biggest proof dealer. If they can find enough guys that want a carbon 8 twist barrel they can get it done. If any one is interested pm me asap. If this happens soon the barrels will be done in January.

Also spoke with carbon six fastest twist they make in .257 is a 9. They told me if I wanted an 7 or 8 I would have to get in touch with McGowen directly and might possibly have to buy them button to make these barrels but I haven't spoke with them yet.

Really hoping the proof deal works out right now as I've had good experiences with their barrels and rifles.

From what it sounds like, it's would really need to be a 7" twist for it to be universally stable at all elevations and velocities, so that might get more sales than an 8" twist .257 barrel.

 

[yorke-1]

From what it sounds like, it's would really need to be a 7" twist for it to be universally stable at all elevations and velocities, so that might get more sales than an 8" twist .257 barrel.

It depends on the use. I've got one of the 7" twist X-Calibers that I haven't done anything with because it sounds like the bullets may not handle 3100+ fps well from a 7" twist barrel. The only .257 chamberings that I'm even remotely interested in will be well over 3100 fps with a 131gr bullet, even from a 24" barrel. I would expect even a 25-06 to get this bullet over 3100 fps from a hunting length barrel.

I'm guessing the design threshold is somewhere around 310K RPMs. 3100 fps from a 7" twist would be closer to 318K RPMs and might compromise bullet performance.

 

[CA48]

From what it sounds like, it's would really need to be a 7" twist for it to be universally stable at all elevations and velocities, so that might get more sales than an 8" twist .257 barrel.

The guys I know that are interested in these barrels which at the moment is 3-4 will be pushing velocities in the 3200-3300 range at a DA of 3500'. 8 twist gives a GSF of ~2.12

If I could get 20 guys committed for 10 1&7 and 1&8 barrels to accommodate cartridges closer to 25 creedmoor velocity's that would be great too.

 

[Conrad]

I'll push these at more moderate velocities via Creed case, be it for competition or a short handy barrel for whitetail. If I'm chasing bigger critters I'm going to step up to a 7 SAUM or 30 mag of sorts...Evolved ballistics is right down the road for me so I'm all for them getting some 1:7 Proofs...in the mean time I'll have to burn out my 20" 6.5 Proof.

 

[sable tireur]

I see no reason to work with small capacity cases when shooting heavy for caliber bullets unless you want to test subsonic loads. These bullets should be designed to deliver all the gusto we can gather from one case.

.257 Weatherby (bore rider freebore)
131 Blackjack
28" barrel, 5R, hand lapped
7.25" twist rate
Two different days (actually PM one day, AM the next)
Just about 400 feet above sea level
89 degrees PM, 45% humidity
81 degrees AM, 68% humidity

First accuracy load PM = ~3280 fps/ 7 ES
First accuracy load AM = ~3320 fps/ 11 ES (different powder)

RPM is around 325,000 approximately. (Bullet RPM = MV X 720/Twist Rate in inches)

All bullets found their way to the target in one piece leaving perfectly round little holes.

Next is to step these out to 600 yards and see what takes place. Then down to the 1,000 yard range for a day of fun with steel and paper. This may have to wait for the work load to diminish slightly...

 

[257 Blackjack]

I see no reason to work with small capacity cases when shooting heavy for caliber bullets unless you want to test subsonic loads. These bullets should be designed to deliver all the gusto we can gather from one case.

.257 Weatherby (bore rider freebore)
131 Blackjack
28" barrel, 5R, hand lapped
7.25" twist rate
Two different days (actually PM one day, AM the next)
Just about 400 feet above sea level
89 degrees PM, 45% humidity
81 degrees AM, 68% humidity

First accuracy load PM = ~3280 fps/ 7 ES
First accuracy load AM = ~3320 fps/ 11 ES (different powder)

RPM is around 325,000 approximately. (Bullet RPM = MV X 720/Twist Rate in inches)

All bullets found their way to the target in one piece leaving perfectly round little holes.

Next is to step these out to 600 yards and see what takes place. Then down to the 1,000 yard range for a day of fun with steel and paper. This may have to wait for the work load to diminish slightly...

Nice load stats.

Which reamer MFG has this 257 WBY Print on hand? Proving to be a good setup I'd like to order one as well since by brother is a big 257 WBY fan and I have his Accumark sitting here waiting for a re-barrel. : )

 

[MudRunner2005]

Looking back in the memory banks... If you're also looking for the same .25-06 AI 40º reamer as I have, I'm about 99% sure my smith had Dave Kiff over at PTG cut it. If you're interested, PM me, and I'll give you my smith's name, so Kiff can look up the exact reamer print.

 

[yorke-1]

I see no reason to work with small capacity cases when shooting heavy for caliber bullets unless you want to test subsonic loads. These bullets should be designed to deliver all the gusto we can gather from one case.

.257 Weatherby (bore rider freebore)
131 Blackjack
28" barrel, 5R, hand lapped
7.25" twist rate
Two different days (actually PM one day, AM the next)
Just about 400 feet above sea level
89 degrees PM, 45% humidity
81 degrees AM, 68% humidity

First accuracy load PM = ~3280 fps/ 7 ES
First accuracy load AM = ~3320 fps/ 11 ES (different powder)

RPM is around 325,000 approximately. (Bullet RPM = MV X 720/Twist Rate in inches)

All bullets found their way to the target in one piece leaving perfectly round little holes.

Next is to step these out to 600 yards and see what takes place. Then down to the 1,000 yard range for a day of fun with steel and paper. This may have to wait for the work load to diminish slightly...

That's encouraging! I was a little concerned by the comments on the Blackjack website suggesting the 8" twist for 3200+ fps applications.

 

[sable tireur]

Which reamer MFG has this 257 WBY Print on hand? Proving to be a good setup I'd like to order one as well since by brother is a big 257 WBY fan and I have his Accumark sitting here waiting for a re-barrel. : )

I'm up to my eyeballs in alligators right now. We have a hurricane bearing down on us so we're trying to batten down the hatches and get everything as secured as possible. I'll check the reamer as soon as I get a minute. Remember, this is a bore rider configuration not your standard throat and freebore set up.

ADDED:

The reamer is a PTG from 4/16.

Bore Rider Finisher

0.285" neck, 0.128" freebore, 1 degree 30 minute throat angle.

That's encouraging! I was a little concerned by the comments on the Blackjack website suggesting the 8" twist for 3200+ fps applications.

Yes. I'm sure that recommendation was to state a best case scenario so folks wouldn't feel pressured into buying nothing but fast twist barrels. But we've been shooting light varmint bullets in standard twist barrels for decades. .25-06 AI shooting 65 and 75 grain bullets in 9" twist barrels. No problem.

Sorry this is short but I have to back up some computers and then pull plugs on the CNC machines.

 

[sable tireur]

Which reamer MFG has this 257 WBY Print on hand? Proving to be a good setup I'd like to order one as well since by brother is a big 257 WBY fan and I have his Accumark sitting here waiting for a re-barrel. : )

I posted this above and here just in case you might miss one...

ADDED:
No print or print number, sorry.

The reamer is a PTG from 4/16.

Bore Rider Finisher

0.285" neck, 0.128" freebore, 1 degree 30 minute throat angle.

Enjoy!

 

[CA48]

The guys I know that are interested in these barrels which at the moment is 3-4 will be pushing velocities in the 3200-3300 range at a DA of 3500'. 8 twist gives a GSF of ~2.12

If I could get 20 guys committed for 10 1&7 and 1&8 barrels to accommodate cartridges closer to 25 creedmoor velocity's that would be great too.

Looking over the numbers again running a 1:8 twist at 3300 actually has a GSR of 1.6 at 1100ft 80* so 1:7 might not be a bad idea but it does put the bullet at 340,000 RPM.

 

[Edd]

Looking over the numbers again running a 1:8 twist at 3300 actually has a GSR of 1.6 at 1100ft 80* so 1:7 might not be a bad idea but it does put the bullet at 340,000 RPM.

Does it mean anything that a bullet traveling 3300 fps and rotating 340,000 RPM's only rotates 3090 times on the way to a 600 yard target.

 

[CA48]

I'm sure it does to a ballistician. I mention the high RPM's because depending on bullet/jacket construction and barrel groves it can cause jacket separation when barrels start getting wear on them which is why they probably reccomened the 1&8 for the higher velocitys .

 

[Swamplord]

Got my batch of bullets last Saturday from the boys at Blackjack Bullets , they are awesome, thanks guys !

Had very limited time to play around with them, work has me heading out of town till end of Oct, maybe longer ... can't wait to see what they will do when I get back

in pic is the 423 Dakota (Lapua) brass cut down, necked down and c.o.w fireformed in the 300 LRC chamber, neck turned in 30 cal to .013" neck thickness per side and then necked down to .257 cal ending up with neck thickness at .014" per side, perfect with no chance of donuts happening !

Rem 700 short action Bottom Metal is cnc machined aluminum by Last Frontier Custom Guns of Alaska with a 5 round WSM Accurate Magazine that fits 3 rounds of 257 Laser ammo loaded to 2.880" coal, leaving plenty of room in mag for worry free feeding up the load ramp in the Rem 700

managed to cut down and neck down 50 pcs of the new Lapua brass in 300 Norma Mag, need to turn necks and final trim then ready for cow forming..

can't believe I'm more excited with the 25 cal over the 6.5, 7mm, 30 cal and 338 cal versions of this wildcat, I think the boys at Blackjack Bullets should call the hunting version the "Black Magic" bullet , y'all put a heeby jeeby spell on us plain folk