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All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Big Bore AirGun Gate => Topic started by: owen on January 18, 2017, 12:21:28 AM

Title: .257 cal 78 gr. NOE Bob's Boattail Bullet ?
Post by: owen on January 18, 2017, 12:21:28 AM

I don't know if there is a thread already about this particular bullet, I searched and couldn't find one, but if one already exists then my apologies for starting another thread. I'm starting this thread though because I'm hoping to get answers to questions that I have about choosing a barrel for these bullets, etc.
Here's a link to this bullet: [url]http://noebulletmolds.com/smf/index.php/topic,1628.0.html/url] I'm looking at R&L's .257 barrels, which have the 1-14" twist. Is this rate of twist ideal for the 78 grain bullets? I know that there are faster rate of twist barrel liners, also. Would 1-12" or 1-10" be a better choice, instead? My barrel length will not exceed 20", so how will that affect rate twist choice? That's all that I can think of, for now.

I tried and tried, but I can't insert the link in my message, here.

Title: Re: .257 cal 78 gr. NOE Bob's Boattail Bullet ?
Post by: K.O. on January 18, 2017, 12:36:43 AM

http://noebulletmolds.com/smf/index.php/topic,1096.0.html (http://noebulletmolds.com/smf/index.php/topic,1096.0.html)


is this the right one?

says 11 twist so 14 might be pushin the slow twist bit... a bit to much...

Title: Re: .257 cal 78 gr. NOE Bob's Boattail Bullet ?
Post by: rsterne on January 18, 2017, 02:04:16 AM

The barrel length does not affect the required twist rate.... The 11" twist is recommended, but it is looking like all the twist recommendations for the BBTs so far are conservative, so it MIGHT work OK in a 14" twist.... particularly if you don't drive it too fast.... Only trying it will tell you for sure.... There is also a Group Buy on the 65 gr. version, which WILL work in a 14" twist....

http://noebulletmolds.com/smf/index.php/topic,1632.0.html (http://noebulletmolds.com/smf/index.php/topic,1632.0.html)

Bob

Title: Re: .257 cal 78 gr. NOE Bob's Boattail Bullet ?
Post by: owen on January 21, 2017, 12:07:12 AM

Thanks, KO.
 Bob, Yes, I already forgot that the 51 gr. NOE BBT was supposed to be for 1:16 rate of twist and does exceptionally well with the 17+:1 LW barrel twist. Yes, I'm planning on getting the 65 gr. NOE BBT mould as well, so I'll get a 1:14 bbl. and just see how both of these bullets work with that. If you want to, maybe you could delete this thread and start a proper thread for both of those bullets, to generate interest and get those two moulds moving forward.

Title: Re: .257 cal 78 gr. NOE Bob's Boattail Bullet ?
Post by: KnifeMaker on January 21, 2017, 04:31:17 AM

Owen, I have that particular barrel, and although I do not have any BT's for it, it is extremely accurate with 60gr, 74 gr, 80 gr and 88 gr. bullets.  ;)

Knife