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Ideal case neck diameter for a 25br

Cloudrepair

Silver $$ Contributor
this may not be the best idea but I don't have money for a new reamer and was thinking maybe just ream a 25br with a 6br and do the neck in a second op
 
No problem doing that, just be sure all your ducks are in a row..
I was thinking a .281 neck diameter is good but want to hear what others think.
Another thought came to me thinking maybe if I used 6.5x47Lapua brass necked down and trimmed to maybe a .400-.375 long neck I could make throat last longer and barrel.
 
this may not be the best idea but I don't have money for a new reamer and was thinking maybe just ream a 25br with a 6br and do the neck in a second op
For .25 Cal., I use .283" neck Dia., and turn necks to 0.0120" thickness, which provides a total of 0.002"
clearance. LAPUA 6BR-Norma (Gold Box) cleans up nicely: .284" neck diameter would work nicely. For no-turn, I don't know a dimension.

With some trepidation, I have used, smaller caliber/same body reamers and then reamed the neck to desired diameter, and then, using yet another reamer, "throated" to "dummy" length - every case has resulted in the barrels delivering excellent grouping. If I can do it, so could a caveman.;) RG
 
For .25 Cal., I use .283" neck Dia., and turn necks to 0.0120" thickness, which provides a total of 0.002"
clearance. LAPUA 6BR-Norma (Gold Box) cleans up nicely: .284" neck diameter would work nicely. For no-turn, I don't know a dimension.

With some trepidation, I have used, smaller caliber/same body reamers and then reamed the neck to desired diameter, and then, using yet another reamer, "throated" to "dummy" length - every case has resulted in the barrels delivering excellent grouping. If I can do it, so could a caveman.;) RG
Thanks
What do you think about the longer neck thought?
Also thinking that I could get away from needing a thoating reamer with the long neck and have .0 freebore but still have enough bullet in the neck.
 
Thanks
What do you think about the longer neck thought?
Especially to accommodate a range of bullet lengths/weights, I prefer as long a neck as the parent brass will comfortably afford, using a minimal free-bore length.

If using something like 6.5x47 LAPUA, or, similar, and forming brass, "the old fashioned way", I'd opt for as long a neck as made me comfortable: the base of the longest bullet I intended to shoot, would always remain in the neck, slightly above (say, .060") the [inside] neck/shoulder junction, while providing sure-fire land contact.

That said, I'd do some homework, and keep the free-bore short enough to also accommodate having, at least .125" of shank of (the shortest bullet) in the neck, while allowing for land contact.

Both the .25BR, and 25x47 LAPUA are quite capable - as would be any wild-cat within this capacity range.
Contemporarily, the big issue would be brass availability. I made some, "LONG-Neck" .250/300 Ack. Imp. which are, "killer good" . . . arbitrarily used the 6MM Remington neck-length: about 0.352". We form the brass from the old Remington .308UBR; or, 7x57 Mauser, etc. If you have a stash of "old-school" brass, go for it and enjoy! :DRG
 
I was thinking a .281 neck diameter is good but want to hear what others think.
Another thought came to me thinking maybe if I used 6.5x47Lapua brass necked down and trimmed to maybe a .400-.375 long neck I could make throat last longer and barrel.

I just read this - GREAT concept!:cool: RG
 
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I don't think my 10.5 twist barrel will stabilize anything longer than the 101 lrx was planing on using or other 100 grain bullets.
For FB bullets, the "ideal" twist for bullets up to about 1.140" long is 1:10"(I always calculate for Std. Sea-level conditions). Stay to that length, or, under, add a boat-tail, and you'll need 1:9" - that's where I finally found magic with my [point-blank] competition barrels.
The first four barrels I tried were 1:10" twist: with my 110 Gr. BT (usually 1.135" - 1.140" long, 0.100" x 10 Deg. BT,) they were, especially in the plains/prarie winds, just OK - NO WOW factor.
So, I "caved" and followed the math - then, All of the 1:9" twist (Bartlein) barrels have proven capable of winning: won a pair of 200s, and a Grand Agg (NBRSA Hunter Nationals) with those, which were chambered .25x47 LAPUA using Henriksen reamer. Wowzer those were GREAT barrels!:D
Back to bullets - it's all about LENGTH - the weight is, "merely along for the ride". There are threads galore debating bullet weight/twist rate. Good shootin'! :DRG
 

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