What a difference 5 grains made

[bebloomster]

Loaded up 10 at 85gr and 10 at 80gr last night and then played hookie from work today. I wasn't able to reproduce the definite group size difference that I had last time so there is a very real possibility that I just got lucky with that cloverleaf group. I did note slightly tighter grouping at 50 yards when fired offhand though with the 80gr load. It might be just my imagination but the 80gr load also seemed slightly more comfortable shooting than the 85gr load... hmm, no secret to that one, 5gr less powder.

Powder was all measured by volume, not weighed. I used one of those brass adjustable ones... probably from Tresco. Just fill it up and level it off, been doing it that way for probably 30 years or more.

Will make up a couple dozen more at 80gr, hopefully getting out to the range again in another week or so.

 

[paulvallandigham]

I have an adjustable volume measure with a funnel attached, that I bought from Tingle. They are now available from Tedd Cash Products. There is enough room between the 5 grain markings to figure out something in between, especially for those of us who used an old fashioned micrometer or vernier caliper, without the 10,000Th adjustments or markers. I still figure out to the 10,000th of an inch when using my dial caliper by reading between the marks.

Depending on how well you consistently throw volume powder charges, you can make a small difference setting the measure between the lines. The Target shooters, however, generally pre-measure their charges on a powder scale- electronic, these days- and bring the separate charges to the range in containers.

Personally, I don't find enough difference with a few grains one way or another when shooting a PRB. However, if you use an OP wad to seal the gas, and get a much lower SDV, I believe that you can see a difference by weighing your charges up or down a couple of grains, at least at 25 and 50 yards. I didn't use to believe this, but my brother's involvement with Chunk Gun Shooting has taught me a few new things I didn't know I didn't know! :rotf: Because I have been primarily shooting BP for plinking, and short range target work, Volume measures to 5 grains was always " good enough ", for me. I remember asking my brother what the heck he was talking about when he mentioned some odd number powder charge. Well, he had the targets to prove he knew what he was talking about. :redface: :rotf: :hmm: :hatsoff:

 

[Isiah1103]

Thanks, I guess I subscribe to the "close enough" theory and also don't worry about a grain or two with PRB in the field shooting. I don't use a funnel when pouring down the muzzle and it's easy to slop around the top or have the wind blow off a few grains. I guess I'm not good enough to tell if the load makes a difference or it's me.

 

[PRM]

Urethra!!! Good shooting, I gotta go on this one.