powder charge diffrence

S

shooter177

CGN Regular
Rating - 100%
49   0   0
Location
Durham region
i just got into reloading and would like to know how much of a difference in powder charge is too much i have a lee perfect powder measure and i find that it can throw charge of up to .5 grain diffrence i understand that it will effect accurcy but what is acceptable .
 
Well, depends on the case. With a light load, say in a 38spl, .5 grains can be a 15-20% variation. 20% low is one thing, 20% high is another. In most medium to large rifle cases, .5 is moot. Some people use .5 grain increments for load development.

How are your reloads performing? You aren't here to look for an excuse for a big group, are you?;)
 
You say---"and i find that it can throw charge of up to .5 grain diffrence"
That's a kind of a mute point, that you "can" make it throw up to ½ grain variance. How accurate is it when you carefully use the same rythm with every throw?
That's what counts. Practice and your variance should be more in the order of .1 to, at the most, .2.
 
H4831 said:
You say---"and i find that it can throw charge of up to .5 grain diffrence"
That's a kind of a mute point, that you "can" make it throw up to ½ grain variance. How accurate is it when you carefully use the same rythm with every throw?
That's what counts. Practice and your variance should be more in the order of .1 to, at the most, .2.
Click to expand...

Is that anything like a moot point? FS
 
I weigh all my charges no matter what I'm loading. They all get weights to the .1 grain. That means that 105.0gr of IMR 4831 in my 470 NE is exactly that. I'm just glad I don't have a scale that reads to the hundredth of a grain...try getting charges perfect with that creature and a standard extruded powder!

I've never used ball of flake powder so I have no experience in blindly trusting my powder measure and only weighing every so often. I'm probably just fussy, but what's wrong with that?
 
I just did some loads today with my new digital scale that is accurate to .02gr.

Talk about overkill. I was dropping individual pellets in to get my loads exactly 44.5gr and I mean exact. plus or minus .02gr

I'm looking forward to seeing the results down range.

The casings were also weighed and sorted
 
Hunter Bench Rest shooters, all load at the range and use powder throw measures of one sort or another.
They don't bring scales to the loading bench for the plain simple fact of wind.
As H4831 says, it's all in the rhythm. There are other factors, like silo baffles and powder level in the silo as well.
Most of the shooters I knew, would throw about 10 charges and return them to the silo. When they dropped the lever, they would tap it against the bottom stop twice, with the same force. This will give a uniform "pack" in the measure receptacle. It will also keep the density in the silo consistent.
If you practise at home, it won't take long to get proficient enough to throw charges within 1/10 grain. In cases like the 6BR, 30BR or 308win 1/10 grain, plus or minus will have virtually no effect on accuracy or pressures, unless you're using an over max load. HBR chambers are so tight that pressures are abnormally higher anyway.

In very small cases or smaller pistol cases, that much variance may not have a lot of effect on accuracy but may have a disproportionate effect on pressures. The type of powder, as alluded to above, will also effect the variances in powder charges.

Ball powder usually works the best in a thrower.

Hand loading can be a real anal retentive hobby. Once you're bitten with the accuracy bug, you will spend many hours on detail. Swaging primer pockets, deburring flash holes, re drilling flash holes for uniformity, turning case necks, bench rest dies, special arbor presses with neck sizer dies that have removable collars of varying diameters. Then of course, you have to buy primers in at least 5000 lots so that they are all from the same lot for consistency, buying at least an 8lb keg of powder, for the same reason and don't forget, buying several hundred rounds of brass so that you can weigh each of them so that there is less than 1 grain difference between the weights, again for consistency. Oh, don't forget to adjust your seater die plunger back a thousandth of an inch or so every 100 or so rounds to make up for throat erosion.

The theory behind all of this is that consistency will give consistent accuracy.

Do you see where the anal remark comes from?
 
It all boils down to how much of a difference in POI you are ok with. Yes there are a ton of variables that influence grouping BUT in terms of powder charges:

Powder, being the guts of the round, is the part responsible for your muzzle velocity (in terms of the reload)

Now differences in that amount of powder will result in differences in the velocity and those differences will be magnified down range and with range those will be magnified further.

So it boils down to how far you are shooting, how big of a target you are trying to hit and how accepting you are towards larger groups.

Obviously for precision shooter who's goal is to produce as small of a group as possible, one would ideally want the powder charge to be as consistent as humanly possible in the hopes of attaining a consistent velocity.

For hunting though or other shooting you may not need be so picky.

For me personally I strive to get my reloads as precise as possible whether it be for target shooting or hunting. the more confidence I have in my reloads the happier I am.


But who knows, maybe I'm just an OCD reloader:redface:
 
For ordinary hunting, where 300 yards would be a long shot, ½ a grain difference in powder for an average hunting rifle is an absolute nothing!
Shooting under hunting conditions a ½ grain, or for that matter a full grain, would not be detected.
I was once building up a 30-06 load with 180 grain bullets and 4350 powder. I took my loading outfit to the range and loaded each cartridge before I shot it. I was loading one shot of every charge and going up one grain at a time. I shot five shots, meaning the last was four grains heavier than the first. I shot them all at a target at 100 yards and when I went to the target I found my five shot group measured 1¼ inches, about all I can expect from a light sporter. As a point of interest, my top loaded cartridge was too heavy and I dropped back two grains for my hunting load.
My rifles are all carefully bedded, so they do not have "likes" or dislikes, regarding such things as minor differences in powder charge.
 
shooter177 said:
i just got into reloading and would like to know how much of a difference in powder charge is too much i have a lee perfect powder measure and i find that it can throw charge of up to .5 grain diffrence i understand that it will effect accurcy but what is acceptable .
Click to expand...

As mentioned before it depends on the case and it depends on what are thrying to achivieve (just hunting or trying to shoot smal groups) In my 22-250 I dont' want half grain differences.....in my 7mm STW I dont' really care......as mentioned the bigger the case and the less difference it makes. In a hunting situation you or the Dead Animal probably wont' know the difference.
 
thanks i am reloading 308 win with varget and had a starting load of 34 grains, i was checking every 3 charges and was getting between 34 and 34.5 ,i never thought of the consistntsy of operator of the powder measure ,i will make sure to try t be consistent
Thanks Shooter177
 
shooter177 said:
thanks i am reloading 308 win with varget and had a starting load of 34 grains, i was checking every 3 charges and was getting between 34 and 34.5 ,i never thought of the consistntsy of operator of the powder measure ,i will make sure to try t be consistent
Thanks Shooter177
Click to expand...


What bullets are you shooting? 34 grains seems awfully low for Varget.
 
For some of the small cases that i play around with ie: the BR series, .300 whisper, 218 Bee, that much variation is unsafe, I weigh every charge. A powder like Lil'gun can run the pressures very quickly and .5gr. variation would be unacceptable and possibly dangerous.
 
ceriksson said:
I just did some loads today with my new digital scale that is accurate to .02gr.

Talk about overkill. I was dropping individual pellets in to get my loads exactly 44.5gr and I mean exact. plus or minus .02gr

I'm looking forward to seeing the results down range.

The casings were also weighed and sorted
Click to expand...

I have a scale with the same accuracy. Some longer stick powders are about 4 kernals = .1 grain. Once you add "individual pellets" and end up with 44.52 a few times, you will learn to ignore the last digit for the most part. Either that or you will have to get yourself a very tiny saw and start cutting kernals in half...:p

Seriously, I'll bet you a flat of beer that .02 grains won't even show up on a chonograph, much less your target.

Unless, of course, your chono is accurate to within .02ft/sec.:D Then all bets are off!
 
Varget pellets come out to closer to .02gr per anyway and It works for me.

I don't care if it shows up on a chonograph or not, I just prefer to have the confidence that my loads are as consistent as possible.
 
You must log in or register to reply here.
Back
Top Bottom