Using Win LP (large pistol primer) for 44 Magnum

[mike100]

I have a new set of dies on the way for 44mag/44Spl and was wondering about compatibility of most published loads with WIN LP (which are said to be for both magnum and regular cartridges).

Are the winchester large pistol primers a little hotter than other large pistol 'regular' primers? Will they ignite slow powders properly? I have about 6k Win LP's for 45 acp so I wanted to build loads off of those. Was thinking about using H110 and Win296 and maybe some unique and ww231 for light loads or 44 spl's.

[Black_Talon]

Only thing I can contribute is that I use WLP for moderate loads (8.5 to 10gr Unique, 250gr LSWC in 44Mag brass) and they work fine. Chronographed velocity is very consistent, SD is sub-10FPS.

Most loading manuals seem to deliberately specify "magnum" primers for most of the hotter loads, but the ones that use WLP for their loads (Speer #13 and the latest Nosler) don't differentiate between standard and magnum primes depending on load type (i.e., they show WLP even for heavy H110, 296 and 2400 loads where the other manuals that aren't using WLP specifically call for magnum primers for those same loads) . This leads me to believe that WLP will work just peachy for heavy loads.

[6079Winston]

I have used WLP primers with both 296 and 2400 in 44 mag, mainly because my Hornady manual said I could. SD for medium loads of 2400 with 240 grain cast bullets and heavy loads of 296 with 240 grain jacketed bullets are in the low 20's. Not outstanding, but probably more than adequate for a 6" revolver. An interesting thing with the 296 load was that there was an abrupt plateau in velocity increases accompanied by a jump in sd as I approached "maximum". x2.0gr 1253fps sd28; x2.5gr 1297fps sd23; x3.0gr 1322fps sd21; x3.5gr 1328fps sd42. Note that for the last 0.5 gr increase in charge weight velocity increased by only 6 fps and the sd doubled, compared to the 50 fps increase and similar sd for the first two 0.5 gr increases in charge weight. One of those days I was happy lugging the chronograph around.

[mike100]

Thanks all for the info. A little something to start with as I'll note both of y'all's real world results. I do have an old 1991 Lyman manual backed up with additional Lyman info in the casting handbook, but I have no other manuals to look through at the moment. I'm torn between getting a real recent one, but I'm afraid the legal dept. might have had a hand in the latest data. I do try to back up load info using a couple of different internet sources though.

If I find a 10-15yr old Speer, Hornady, or similar book at a gunshow or wherever, I'll get it.

[Franksremote]

WLP primers are fine for .44 loads. If loading hot, then watch for pressure signs (flattened primers, etc.) and adjust or exchange primers accordingly (a different powder is also an alternative). Most loads with WLP are going to be fine as the cup isn't much (if at all) different that WLPM or WLR, just the compound that causes ignition. I've used regular SP primers in hot 9 major rounds without issue, WSR is there as a buffer, just in case. Load away