Good evening gents,
I'm sorting out a full stock Interarms, Zastava made, 7x57.
I only mention full stock due to my suspicion that I have not truly free floated the barrel, shots stringing right to left 3/4"-1" apart.
The 8.5 rate of twist has me loading Hornady 162 gr over various charges of H4350, with no luck.
I understand that the European manufactuers will often have a very deep throat on their barrels for 7x57s to accomodate the original 175 gr. RN bullet.
That said, I started looking to seating depth to try to improve the accuracy. I did the sized case with loose bullet and it is measuring 3.090" long on the lands. Believe the books say 3.000" COAL.
Is this too long to back off .015" and try?
Looking for pointers if anyone has been down this road before?
I can always load at 3.085" and reduce charge, but that leaves a lot of empty case. I could/should fill that with powder. Curious to see what y'all say.
Thanks

It's okay to seat longer than the suggested OAL, as long as you understand that you might exceed the length the magazine can accommodate AND if you are "very close" to the lands you may create a bit higher pressure than you would experience otherwise.

It's probably better to seat at least about one caliber into the neck, meaning that a .257-inch bullet needs to have about a quarter inch of shank in the neck. That's just a guideline, nothing magic about it. A little more or a little less won't mean much.

Don't worry about getting the bullet right up against the lands for accuracy. There are usually several sweet spots in seating depth and you might find one as far as 0.100" or more off the lands. You just need to play with it some.

On that Hornady---don't beat your head against the wall too long. If you keep getting awful groups no matter what you try with it, move along to another bullet just to see that the rifle will shoot. Sometimes they just won't shoot the bullet you hoped would work. I've been down that road with Accubonds in three different rifles. Luckily Accubonds worked out for me in at least one rifle. They were so bad in one of my rifles I thought I had a busted scope, but when I went back to Partitions everything was hunky-dory. Other guys have great luck with 'em. You just gotta be willing to move around a bit sometimes, if for no other reason than to verify your rifle and scope, and to keep your confidence out of the toilet!

River Rader, thanks for the information.
I'll try deep seating to see if the 46-47 grains for powder starts to sort out.
I'm determined to look at my bedding issues as well.
The magazine should feed just fine due to the fact that this is a true long action with an intermediate length cartridge.
If/ when I meet success I will share.
Thanks again!