questions about different weight cases

went back out and shot 300 yds today. most of my loads were winchester brass. i also took some remmington brass for comparison. the remmington cases weigh about 6 grains heavier. everything was loaded exactly the same. the winchester rounds would shoot real close to MOA with one weird flier. not sure why it does that. i may be loading them too hot. the rem loads would almost group but have two or three hitting the target several inches out. this was with 5 shot groups. now, im assuming i could back off the charge on the heavier cases but no idea how much. anyone experiment with this?

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I’ve never experimented with different types of rifle brass. However, I have noticed a difference between the various brands of pistol brass. Some are definitely thicker than others. I can feel the difference when crimping. Therefore, I always sort headstamps for my semi-auto loads for better consistency. Revolver loads are more forgiving, so I load mixed brass for plinking.

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Assuming your loads are near maximum, try loading several different batches, backing off the powder charge maybe 2 or 3 tenths of a grain with each batch. Might fix your problem, it might not. I’ve found bullet seating depth and using neck sized fire formed brass to be very important to consistent accuracy. Sometimes it takes a while to come across the right combination. You can also try setting aside (culling) the cases that give you fliers. Could be as simple as that.

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looking back through my Vihtavuori load book, im at max load at 44 grains. the book i have doesnt show a starting load, just the max. i definitely need to back down a bit and see what happens.
58marine, i agree i think i need to load up several batches and set up several targets. im not sure how to figure out which shot is the flier. at 300yds, i cant see the holes with any of my scopes. i think it might be the last one. maybe from heat in the barrel? i did one 4 shot group and didnt seem to have the flier but i didnt confirm that with another 4 shot group.
SteelPinger, you got me to thinking… when i sized the Rem brass, i can feel a definite difference sizing the neck. if tension there is significantly tighter then pressures will be higher. i need to check that.

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From my experience, you can work your loads up at 100 yards. If you get 1/2" groups at 100, you’ll get 1" at 200, 1 1/2" at 300, and so on, more or less. If you can’t see your hits from the bench, it’s time for a good spotting scope. (It’ll save you a lot of walking, too.)
And this goes out to everyone, especially new reloaders. Don’t start off with max powder charges. Work your way up, slowly. Look out for signs of excessive pressure.
“That’s all I have to say about that”

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I wouldn’t think case weight would make any difference since you should be loading by powder weight.
And as 58marine said start low and work up.
Flat primers are the first sign, sticky cases the next.
Each gun is different and each also has a sweet spot where the pattern tightens too, then starts expanding out.
In my experience with my rifles, that spot tends to be somewhere between 75 to 85% of the max loads or where I see flat primers.
Takes a bit of experimenting with different loads to find that spot.
Your groups will tighten incrementally and then start expanding as you increase loads.
And your buddies gun may be the exact same gun and that spot will be at a different load.
Take Notes as you go out shooting and send at least three rounds down range before you start logging results.
Pressure is not your friend.
Use this as a guide to where you may be.
http://kwk.us/powley.html

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well, obviously i need some recommendations on a decent spotting scope. all of mine are crap.

the pressure concern is why i was asking about the different weights. if its thicker, it has less volume. i just dont know how critical that is. i think my issues are because im at max charge. hopefully i can get back out to the range this weekend and try with reduced loads. if not, it will be 2 weeks since my racing habit is interfering with my shooting addiction.

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If the outside dimensions are the same the heavier brass should have smaller inside volume. Smaller volume higher pressure. I sometimes have flyers in my groups. Some are my fault. Some I think are the quality of the projectiles. I don’t buy match quality projectiles for my range ammo. With Nosler balstic tips in my bolt gun and about 3 grains below maxim with Varget I get sub 1/2 MOA groups this is my hunting load. My PA10 also likes this load but only shoots just under 1 MOA with it. Since I don’t anticipate any shots over 300 yds I can live with a little less velocity with the lighter powder load.

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