Benefits of seating out long in 300 win?

[gsteve]

I have a sako s20 coming and I understand they have designed the mag to allow a longer oal. What kind of FPS gain can I expect with the heavier bullets. 200-220 gr ? And is there a loading table ?
Thanks

 

[gsteve]

I should state that I know a FPS gain will require more powder than a standard oal and that a bullet closer to the lands has a potential for more accuracy. I'm curious about the FPS gain.

 

[Wolf76]

There's no specific way to say you'll gain X fps. You literally need to test it for yourself because there are too many variables.
Perhaps the biggest difference is running more/slower powder to push heavier bullets. There's no substitute for case capacity - regardless of marketing.
It's commonly accepted there's no benefit to having the bullet in the powder column. You have a magnum, don't handicap it.

 

[DoneNOut]

I should state that I know a FPS gain will require more powder than a standard oal and that a bullet closer to the lands has a potential for more accuracy. I'm curious about the FPS gain.

Thats a weird one. My most accurate load is .120" from the lands. I try to keep the base of the bullets right even to where the neck meets the shoulder. Depending on length and brand of bullet this isn't always possible, but its a goal.

That's great the mag is made longer! I have to single feed my Savage 110 300WM if i want to go further than 3.5" mag length.

 

[JMW67]

All you can do is get some H-1000 and RL-26 start loading and see where you end up remember the barrel will speed up after a number of shots

 

[DoneNOut]

All you can do is get some H-1000 and RL-26 start loading and see where you end up remember the barrel will speed up after a number of shots

That's a big 10-4!

 

[cape cove]

I have a sako s20 coming and I understand they have designed the mag to allow a longer oal. What kind of FPS gain can I expect with the heavier bullets. 200-220 gr ? And is there a loading table ?
Thanks

Longer mag will help but it really depends how your throat is cut. Will you be able to take advantage of the longer mag length.

 

[Dmagna]

I have a custom throated savage and push 215s to 3000 FPS in a 26 inch barrel with H1000. But it's being pushed hard.

 

[Jester560]

I have a Sako M995 and am seating to 3.560 col. That is .040 off the lands. This gives me 1/2moa to 800 and 1 moa to 1800. It may be me why it doesn't group better at longer ranges
My load is not a barrel burner at 2850 but is so sweet of a shooter.

 

[MagnumManiac]

With a mag box length of 3.7" and only the heal of the boat tail below the neck/shoulder juncture, I am at 3.610" with 210 ABLR, 3.635" with 210 Berger in one rifle and .010" different in another two rifles. All are high end Rem 700's, Sendero, LR and 5R custom shop.
This allows around 100fps gain over the same bullets in a 3.400" mag box.
So, yes, longer seating allows higher velocity before reaching max pressure.

Cheers.