I recently received a FA83 in .475L and am curious about which primer to use. Some load data shows pistol primers and some shows rifle primers. I know the first .475's were from 45-70 cases and that may be the reason for the difference. My cases are Starline. Thanks for your help.

Winchester WLP primers are all I use with all powders. John Linebaugh will tell you that the use of magnum primers just raises pressure so stick with WLP. I've been using the standard WLP in all kinds of weather from 20-30 below in KS some years to the warm 100 plus degree days in Mississippi during the Summer months and never had a problem. Shot some as recently as two weeks ago down there when I was home to visit

How far North along the River are you located down there?

Federal mag match because they were all I could buy to use with 296/H-110. I also have Fed. and Win. LP primers for #9 and HS-6

Thanks, I loaded some test rounds with CPB 410WFNGC and H4227 & H110 with WLP primers and was just checking before I went much farther. Right now the 4227 has tighter groups but the 110 is a hotter load and is showing better potential but I haven't quite got it right yet. The 110 shoots great in my 480SRH so I guess I've got some fine tuning to do.

H-4227 is another good powder. Use that powder for my 454 "whitetail load". Very accurate which is key for shot placement....

I believe large pistol primers are the way to go also. Just make sure you are getting positive ignition.

Put 14 grains HS6 behind that same slug and the WLP and it should do about 1100 ish. The load is very pleasant to shoot and is usually very accurate. Haven't found a deer or pig yet that cares for it though

Another that I've really enjoyed working with over the last couple of years is the 385 grain HP from the Miha mold we did a while back. Sixshot sells them at about 9 BRN which expand really nicely and hold together perfectly, and they don't lead at 1100 fps but they do a lot of damage. I had full penetration on a large bison at 1150 fps at 50-55 yards behind the shoulder with 1" perfect holes in both ribcages. James has used it on hog also. I'm planning to use it in my 475 FA this year for deer and hogs as well. Just another slug you may want to check out....

I have two FA's in .475, one a custom cut 5 3/4" and the other a 4 3/4". I agree with GlennS you can't go wrong with WLP and use it for most of my light to medium loadings. But when I get into powders of the Win 296 category and want to push my bullet a little faster I use a large pistol mag primer like Federal 155.
Here are my findings:
A. 5 3/4" barrel 15.0 gr HS6, CPB 410gr WFNGC, WLP = 1104 fps spread of 13fps.
B. 4 3/4" barrel 15.0 gr HS6, CPB 410gr WFNGC, WLP = 1091 fps and spread of 21 fps.
C. 4 3/4" and 24.0 gr of Win 296, 400gr LFNGC, Fed mag primer = 1100 fps, spread of 16fps.
I find these loadings great for hunting just about anything.
Hope this is helpful.