Got a question for you guys. I load 129 gr hornady SP's in front of 46 gr 2209 with an AOL of 74 mm, getting 1" accuracy @ 50 metres, thought will try setting projectile closer to the lands. Put a dummy shell and projectile in my rifle closed the bolt then opened it and measured the AOL which was 80mm, fine, I reduced the length to 77 mm and had a go with these they were consistently in a 3" range @ 50 metres. Can you shed any light. What would cause the loss of accuracy as I understood it if the projectile was closer to the lands accuracy improved.

Decreasing the distance to the lands often increases accuracy, but in some cases there is no change, and sometimes it gets worse, as you have just noted! Accuracy sometimes improves when the round is shortened, as well. I had a .375 H&H Magnum that shot best with rounds UNDER factory loaded length!

Since all rifles are individuals, all you can do is to try different things and see what happens. Since you now know that increasing the length of your loaded rounds has a detrimental effect, I suggest you now go the OTHER DIRECTION, and shorten them some from the 74mm AOL. Try some @ 72mm, and some at 70mm and see if either of these lengths improves your groups.

Never change more than one variable at a time. Keep the bullet, powder charge and primer the same when you change lengths.

Try them at parallax-free-distance. 100m? 100yds?

I wouldn't expect improved accuracy from seating to the lands with that bullet in that caliber. Too long throat/too short bullet.

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posted 11 January 2005 15:30
Decreasing the distance to the lands often increases accuracy,

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This is the common wisdomm I agree but have yet to see difinitive tests to confirm such.

It's frustrating to see folks trying to fix 3" groups at 50 yards by trying to adjust the bullet "jump" to the lands.....it's like going to a proctologist because you have a toothache.

you increased the OAL by 3mm,.therefore you increased the internal capacity, therefore you decreased the pressure, sooooooo add some powder!!

next,..50yds means NOTHING at all in load developement.

third,..closer to the lands than factory or SAAMI has always produced better accuracy for me. But,..I am loading for that set-up,..therefore the loads I find will be for a close to the land load,..not a 1 mile jump to satisfy all the lawyers out there.

I agree with JustC. I load my 6.5 x 55s to an OAL of 80mms.

I believe 2209 is the same as Hodgdon H 4350 if I am not mistaken. If so, I have found the best accuracy with that and a 129 gr Hornady bullet to be at near max velocity, otherwise it goes to hell in a handbasket quickly.

I also found that powders a little faster, like IMR 4064 or RL 15 seem to give the best accuracy. I have tried H 4895, Varget and H 4350 in my rifles and none of them gave very good accuracy in the 6.5 x 55. I know those are all The ADI powders. Benchmark also with varmint bullets did not do well.

I own 6.5x55s in a Ruger, a Winchester Model 70 and a Karl Gustaf 1920 production.

Just passing on my experiences.
Good luck.
Cheers & good shooting
seafire

Thanks Guys

El Deguello: thanks for that I will try going the other way and see if it makes them better.

Ollie: I will push the target out, I was aiming appro 5mm high at 50m so that the bullet travelled back down through the line of sight at 150m.