Shocked over diff in 1 grain

02-19-2006, 09:32 PM

I have seen it dozens of times and still shocks me how much difference a 1 grain difference inpowder charge makes.

I got .7MOA at 200 yards with 74gr of 7828 and 160gr accurbond with my STW. I got over 1.5MOA at 200 with 75. I see it time and time again. My 45-70 with 46gr of 4198 gets 1.4MOA over and over but over 2MOA with 48gr. Really makes relaoding seem worthwhile.

biscuit jake · 02-20-2006, 07:21 AM

Well that is interesting from the standpoint of how much powder you have to dump down an STW to start. I wonder what the effect would be if the priming charge could be more in the middle of the powder instead of the base on tall column charges. But that is star wars, biscuit.

02-20-2006, 08:14 AM

Quote:

ORIGINAL: biscuit jake

Well that is interesting from the standpoint of how much powder you have to dump down an STW to start. I wonder what the effect would be if the priming charge could be more in the middle of the powder instead of the base on tall column charges. But that is star wars, biscuit.

Sorry, don't understand what your talking about? Maybe explain.

biscuit jake · 02-20-2006, 10:33 AM

The primer has a tall column of powder to ignite. I wonder what changes we might see if the initial ignition is more central.

02-20-2006, 10:38 AM

There were a few manuf doing some eperiments with that a long time ago. I don't think it came out to be any significant. On my inline Muzzeloader,I have a breechplug that ignites teh powder towards the front. It made my accuracy improve with larger charges.

North Texan · 02-20-2006, 10:41 AM

I think a lot of it depends on case size. I've seen a lot of difference in my .223 with just a few 10ths of a grain difference in powder. Of course, it just handles 28 grains max to begin with.

Ought Six · 02-20-2006, 11:12 AM

If the primer was more central you would see that same affect as using too little powder in a bottleneck case....too much powder ignites causing a massive pressure spike.

charlie brown · 02-20-2006, 03:54 PM

biscut jake - They have that thought already in place. Its all in the Short Magnums. Put the same amount of powder, or less actually, in a shorter, fatter case, andyou get more uniform ignition, and in theory faster velociteis and better accuracy with less powder burned.

haugenna · 02-22-2006, 02:56 PM

Big,

Have you ever done a ladder test with a gun? You will be extremely suprised with what .2 of a grain will do in a charge.

02-22-2006, 03:01 PM

Yea, I tried the ladder thing a few years ago. but I found it to be very inconclusive as most people have.