Pac-Nor .298" barrel w/ 13" twist

[wmitty]

This is on Flea-bay; why a .298" land diameter? How would this work for, say, the RCBS .30-180 SP? Or is the twist rate too slow for that long a projectile?

How about the 311466? Any thoughts?

[B R Shooter]

A lot of high power long range shooter like the "tight" bores. Don't know if there is something to it or not, my money would go to a .300" bore. In the j-word world, you could go up to about a 175 grain bullet.

[Love Life]

Tight bores give more velocity with less powder. Well, that tends to be my limited experience.

[DCM]

Many "Palma" shooters love the tight-bores.
I have 2 tight bore Palma take offs sitting here waiting to be set back, plenty of meat and life left in those 30" barrels.
For the right price I would buy it.

[country gent]

That also may be a 3 groove barrel as at one time that was pac nors specialty. Alot of palma shooters used 1-12 or 1-13 twists and barrels around 28=30" long contoured to make wieght. Chambered in 308 they were very formidable rifles to compete against at 600,800,900, and 1000 yds when built right.

[Larry Gibson]

the RCBS .30-180 SP? Or is the twist rate too slow for that long a projectile?

Does fine in my 14" twist Palma barrel. The 311466 does extremely well in my 14" twist also. Target is that bullet at a tudge over 2600 fps; 10 shots at 100 yards. Holds very well to 300 yards also. Might not get 2600+ fps with such accuracy potential as things are "getting up there" but I'd bet 2500+ fps from a .308W in that barrel (if still over 26") with excellent accuracy would be quite probable.

Larry Gibson

Attachment 107509

[Multigunner]

Tight bore target barrels reduce blowby when using boat tail bullets, but testing has shown that they also raise chamber pressure. The tight bore itself doesn't raise pressure very much but the throats are usually cut tight to match the bore and thats the real culprit.

Experiments on British made tight bore FN FAL barrels showed a great increase in usable bore life, barrels lasting from 30,000 to 50,000 rounds before accuracy was compromised.