After my "pressure testing" indicated that using an improvised cotton filler improved the pressure curve, I ordered some foam wads. Spent a few hours shooting in the rain today and found that when I use a foam wad with my load of 105 Grs IMR4831 I increase the velocity from 1979 to 2080 and this has every indication of giving a better group. I got rained off before I could finish but last two rds made an inch at 100m. Federal 215 primers Jaminson brass and 500 Gr Woodleigh SP. I would estimate that the wad was compressed by about one third of its length.

Any one else found this to be true?

John

John, what load are you using with the 4831? I use Rel 15 and found that foam wads gave more consistant velocity.....

I was using 105 grs IMR 4831 as per Graeme Wright and many others.

I have just started to "play" with RL15 but my Vaughan does not seem to like it!

John

I used 89 gr of RL15 with a 500gr NF CP and 90 gr of RL15 with the Woodleigh soft (500gr)...both with foam filler. Both shot within 25 FPS and grouped (regulated) perfectly at 60 yards. I actually put 3 rounds of each (6 total) in 3.5" at 60 yds off the sticks just before I left last fall. This was in my Merkel...but each gun is different. I'm partial to the RL15.

Gary
DRSS
NRA Lifer
SCI
DSC

Gary hit it on the head. each gun is different. I use 88 gr. Rel 15 in my Krieghoff for 2108 fps

Yes, adding filler to a load adds velocity almost like adding the weight of the filler as extra powder.

I found that using a heavier, more dense foam wad added more velocity (and uniformity) than adding a low density wad, though both were of the same volume when the wads were not compressed.

When you really wise up you will be using H4831 (either SC or "Long Cut," whichever works best with your particular bullet) instead of IMR4831, for the reason of better temperature insensitivity with the H4831, and excellent performance in all other parameters as well.

H4831 will work great with no filler and about 5 grains more powder than the IMR-4831.

Yes, every rifle is different, and loads need to be tuned to the rifle and ammo components. The folly of using generic factory loads in all 470NE's is suggested by this concept.

quote:

Originally posted by RIP:
. The folly of using generic factory loads in all 470NE's is suggested by this concept.

Not to mention cost!

I was wondering why build up a load that would need any filler? As mentioned here using H4831, a memorial load in a member's honor, requires no filler. I agree now with all that the air space in the Federal factory loads is unacceptable. The regular Norma 470 I just got has no airspace and Norma tells me no filler is used. With all I've learned here from all the great info offered by so many, I would not roll my own with any filler.

George Hoffman loads his 470NE with H4831 in the Happy Hunting Ground, just like he did while he was here amongst us: +/- 110 grains

I imagine the supply of H4831 is never ending there, what with Jack O'Connor using the same powder in his .416 Rigby: 105 grains exactly

Saint Saltpeter surely makes regular H4831 deliveries to the Happy Hunting Ground.