I have a (new) heym 88b 470 with 24 inch barrels that I am working up loads for and I also have a new Chrony Beta- that I am using to do this and I am abit paranoid about these things as this is my first time reloading for the Big NE's and my first double, so I wanted to consult the accumulated wisdom here. Is there an absolute maximum amount of R15 I should stick to with the 470NE?

My load right now is with full length resized once fired norma brass,500 gr woodleiegh softs, 93grains of R15, and a kynoch foam wad.I had to use winchester magnum primers because the federal 215's are impossible for me to find in ontario. I decided not to crimp-My brass comes out of the RCBS dies (expander removed) with a Neck ID of .467" (.007 undersize) and seems to grip damn tight.

This is chronoing about 2080fps (I have checked the chrony with factory norma 500grain solids and they are at about 2175-2200 fps).

I started at 86 grains (1920 fps) and worked my way up from there. At 93 grains my left barrel still shoots 2" to the left- The right barrel is darn close to where it should be (this is at 30 yards). I am sure if I keep going that the left barrel is going to come in towards poa and velocity will equal the norma loads.- I figure at about 96 or 97 grains.


I am however starting to get abit nervous as I see most loads are listed under 90 grains- and on steves reloading pages 90 grains is listed at the max. If my chrony says 2080 and the left barrel still wants to move towards the POA should I keep going up till 96 grains or am I creating a questionable amount of pressure here?

I am wondering if the difference could be in the primers as most use federal?
How much difference would it make in velocity if I started to crimp?
FYI the gun was regulated with federal 500 grain trophy bonded at the factory

(PS-my hats off to you guys that are shooting stuff bigger that .470- Holy hell these things KICK- I'm damn sure my biggest gun ever is going to be a .470. Makes it real nice to go back to the .375 after half a dozen sighting in shots with this thing.)
Thanks for looking
Dan

www.470mbogo.com
nearly identical case capcaity - but NOT SAFE loads for a double

So does that mean that you think I would be safe @ 96 grains or no?- Think I will rephrase my question to clarify.
thanks

I thought I was going over with Steves Loads. Well I went .5 of a grain over. But if I were you I would come down some sounds like you are using alot of pressure more then the rifle was made to handle.

You should post this question on the double rifle forum here at AR to make sure you get exposure to those who regularly load for the 470.

I would rely on velocity, btw, but have NO experience with the 470.

JPK

NOTLIM- I'm gonna save you alot of effort. I own and have hunted with .470NE,s and this load has been tops in three of them. I dont like fillers in general and or Rl-15 in doubles because with it you need fillers. YOU MUST always CRIMP TOO or you velocity variations will be more than acceptable..
Try 106 gr of H4831SC a 500 gr Woodleigh, soft/solid or brass banded Solid, Fed 215 primer, CRIMP. This load uses no filler and shot through an ELE broadside. In my Searcy .470NE it shoots 4 shot 1.5 inch clover leaf groups.-Rob