6.5x284 seating depth [SAVAGE "F" CLASS]

[300ultramag]

I hope i am in the right forum.I own the above rifle and have been building some loads for it and have had fantastic results with H4350 and also H4831Sc behind 142SMK's.my question is the incredibly long throat of the savage rifle.i have learned over the years of handloading that you should have at least the bullet dia in the case but my best loads are with .020" jammed in the lands that leave only .125" of bullet in the neck,that is not counting the taper of the boat tail,my question is ,do you think that is enough bearing surface?? i have avg. .187"-.250" groups with this oal but am a bit concerned about so little bullet grip in the case mouth so i seated them an additional .100" giving them a .225" in the neck but my groups have opened up to 1/2". on another note i am disappointed with my velocity as i cannot reach the 2950-3000 fps that his caliber is famous for.i have had good luck with 53.2Grs of H4831Sc but velocity is only 2850 fps. using my CED millenium chronograph and i also have a sweet load of 49.3 grs of H4350 but again only 2800 fps.i am not that impressed with the velocity as i sold a custom built 6.5x47L that put 140 bergers in at 2850 fps and shot .375" all day long.Getting back to my original question is that enough bullet in the case for consistent accuracy??i am worried with so little bullet under tension in the neck that runout could be a real issue.i guess using a 140gr. vld and touching the lands is out of the question unless i have the chamber set back. i plan on using this oal for "F" class shooying in the spring

 

[fullersson]

I agree with you a bullet should be seated at least the depth of the bullet diameter. That is an older line of thinking but a good line of thinking. All that being said I wouldn't be afraid to try it but I would keep a close eye on how things were progressing. Brian Brown.

 

[TonyR]

I would let the results on the target with your gun decide for you. I try to have my barrels throated as is generally recommended, but I have had excellent results with bullets seated barely in the neck so I think accuracy depends on many factors other than just the bullet shank in the neck.

 

[watercam]

That throat is not your friend! If you are single loading to fire, the shorter contained bearing surface should not hurt you (if you are using a sliding type seating die). If loading from a magazine then seating deeper would be advised. Have you contacted Savage about this? If you have a 30" barrel you should definitely have faster velocity with that load of 4350. In my rifle I am attaining 3000 fps w/ 47.5 gr.. Not sure how they would have buggered up your chamber if all else is working - but that seems to be excessive free-bore.

 

[expiper]

listen to your gun...if it is shootin 1/4" groups with em jammed....then I wuldnt change a thing....as Tony said .."the targets will tell the tale".....I have single loaded many rounds with only .060" (that is sixty thousands) of shank (bullet grip) with no problem...but I feel better if the shank is around .080-.100".....if you have .125 of grip you shuld be fine...if you are worried try to pull one of em with your hands...if you can go .001 titer on the bushing....the "old wives tale" of a bullet dia of grip is "just that".....Roger

 

[nosualc]

300um,

What's your ES and SD? How does it shoot further out?

Like the other guys said, if you're getting 1/4" groups at 100 with a low spread and SD, and your groups hold up at 300 or more, then I would roll with it. Be gentle with your loaded cases and don't let the lower than expected speed bother you.

I had the same problem with my savage f class rifle in 6.5x284. From the factory, the stock barrel was throated similarly long. In order to touch the lands with the 142SMK I had to seat things so far out as to to have very very little bullet in the case. In my case so little that I could wiggle the bullet with my fingers. With the Berger 140gr long range bullet, I believe that I couldn't touch the lands at all. I didn't try Berger 140 VLDs (I couldn't find any locally).

I found a load seated further in that would group around 1/2", and I used that for half the season last year. I was seeing 2900 fps with an ES of 25, if I recall correctly. Worked ok @ 600 yds, but would give me some real wild fliers (eg - an occasional 8 ) and the barrel was quite a chore to clean. The cleaning was annoying, but the fliers really started to frustrate me.

After 300-400 rounds, I got tired of chasing my tail, and screwed a Criterion pre-fit barrel on. I can easily touch the lands now, and my current load (140gr Berger VLD, 50.8gr 4831sc, seated .020 into lands) gets 2950 fps with a ES of around 10. My scores went from 190-192s to 196-198s @600.

Good luck!

-nosualc

ps - Regardless, I'd order another barrel now. They're like tires on a muscle car.

 

[FNfan1]

Thanks for the info. Is everyone here using a standard 6.5x284 Norma chamber?

 

[300ultramag]

Thanks for the help/feedback guys: I was planning on using 142 smk's exclusively as Bergers,and JLK's are hard to come by in my neck of the woods.my e.s and s.d. were single digits with them jammed .020" after setting them back my groups opened up tp 1/2" but when i moved out to 300 yrds my groups were 3 1/2-4"" i was very discouraged to say the least.i now have decided to stop shooting at anything less than 300 yrds my next loads will be .020" jammed and see if this tightens my 300 yrd groups,i was expecting 1 1/2-2" at the worst. :'(