What makes a.45 acp +plus load ??

[HunterGreen]

Hello there hope everyone is well.


First time I loaded .45 acp in my camp .45 marlin.

Loaded 230 fmj .451, hodgon 700x powder 5.3 grains, cci large pistol primer.

I was a bit disappointed with velocity. Book calls for 4.9gr of powder for 842 fps.

I am only getting 881fps out of 16 inch barrel ????? Why ??

I expected at least 1000fps.

In other words, what how many more grains of powder it takes to be plus +p

 

[Lefty7mmstw]

You are burning so little powder in the 45 acp that your max velocity is likely reached by 8" or so of barrel length (your pressure is dropping to the point where you can't actually push the bullet faster as bore drag is stalling acceleration), especially using a powder like 700x, which is actually a bit on the fast side for full performance loads with that cartridge.

I would think of using a powder like AA #7 if I wanted max velocity out of the 45 acp in a bit longer barrel, instead of going over book loads for the given combination. Also look for +p data, as it is loaded to a bit higher charge weights and hence pressures... That will net you a bit more speed while staying with tested data.

 

[HunterGreen]

You are burning so little powder in the 45 acp that your max velocity is likely reached by 8" or so of barrel length (your pressure is dropping to the point where you can't actually push the bullet faster as bore drag is stalling acceleration), especially using a powder like 700x, which is actually a bit on the fast side for full performance loads with that cartridge.

I would think of using a powder like AA #7 if I wanted max velocity out of the 45 acp in a bit longer barrel, instead of going over book loads for the given combination. Also look for +p data, as it is loaded to a bit higher charge weights and hence pressures... That will net you a bit more speed while staying with tested data.

Great advice, thanks lefty.

Btw where can I find +p load data. None of my books has it.

 

[Lefty7mmstw]

I was perusing my data books and I only have found +p data for a couple of hodgdon powders out of an older manual. p.m. me if you want the data... it is for hs6 and hp38...
I have seen a lot more data for the 38 special with +p loads than that...