OAL factory chamber way off Savage F class

[fiftycalforsquirrels]

Maybe not way off for a factory chamber but...

I've got a second hand Savage F class 6.5x284 and I'm trying to figure out a starting load for it.

Previous owner suggests a 142 SMK @ 3.246 OAL @ 49.5 4831sc.

I picked up some 140 SMK's and I understand theyre slightly shorter base to tip than a 142.

I stuck a hornady OAL gauge with mod shell in my rifle with a 140 SMK and it measured a way long free throat. Like, .170" based on .100" seated projectile. (Bullet was sticking out .070 until the boat tail will be taken up, then added on .100 actual seating)

.170 jump will put me at 3.167 OAL.

Book spec puts a 140 SMK at 2.830 at 47.5 max RL22(powder I have on hand)

Book OAL for the 142 suggests a 2.910 at 48.2 of 4831sc. So prev owner was .336" longer than suggested and 1.3 over max.

Can I safely load my initial round at 3.167 and say 48.5 rl22?
Assuming .100" seat tension is enough? Barely...

If I load to suggested OAL, then I'll be at .507" jump. Not sure what thats all about. Honestly thought I'd have enough play put it
010" into the lands. Nature of a factory chamber??

 

[maynard]

OAL means nothing unless you need to feed from a magazine. Measure 10 bullets out of the box and see what I mean. The 6.5X284's are barrel burners. I know a guy that used to have 2 barrels fitted every year to get through the season.
I would seat the bullets at least one caliber into the case and try it from there.