your input please and thank you

[motodog]

ill make it short.using the hornady bullet comparator and o.a.l guage i measured my chamber with a 154 hornady sst.i repeated this step 10 times and devided by 10 to get my average.i came up with 3.647 oal. i want to build some rounds this weekend and was wondering if i made the cartridge to a oal of 3.645 do you think it would shoot fine.rifle is 7mm rem mag weatherby sub moa. i have a 140 berger vld round that shoots to 300yrds great just want to experament with other loads.oh yea i will be using ramshot magnum powder. thanks for your time

 

[Suasponte]

Re: your input please and thank you

That seems pretty long. It has been my experience with Weaterby's that they have a lot of free bore. This means there is a significant amount of space between the end of the chamber and where the rifling starts. Most every Weatherby I have I cannot load out to touch the rifling.

How much of you bullet appeared to be in the case when you took the measurement?

All my Weatherbys are loaded to the recommended length in the manual.

Terry

 

[Rick_3]

Re: your input please and thank you

Most Berger's want to be shot on the lands. You may want to check and do ladder tests with powder loads to make sure that you do not over pressure the case by putting the bullets so close to the lands. Pressures may be great further out the bullet is, but accuracy may suffer. I try the ladder tests with powders, and then test for length going out .005 at a time.
Good luck!

 

[motodog]

Re: your input please and thank you

by measuring .597 is in the neck of the bullet neck. using calipers i have a overall measurment from base of round to tip of bullet of 3.269. the book tells me c.o.l. of 3.290.

 

[Rick_3]

Re: your input please and thank you

You need to load the round and see if there are any problems with the round fitting in the mag also. Most COAL is limited by mag length. If it will fityou are good to go.If the lands are hit at 3.269 COAL the start by trying about .o18 off the lands. This generally works with alot of different bullets, that is except Bergers.

 

[motodog]

Re: your input please and thank you

yes bergers are a finicky bullet to load i got lucky and found a match for my 7mm without alot of loading. thank you very much guys.

 

[Victor N TN]

Re: your input please and thank you

Just a friendly reminder. If you put a bullet into the lands, don't try to remove that round from the chamber. Sometimes bullets stick in the lands and the bullet comes loose and the action gets filled with powder.

 

[Fuzzball]

Re: your input please and thank you

"..if i made the cartridge to a oal of 3.645 do you think it would shoot fine."

Well, it will shoot fine. Likely to shoot more accurately if you back off .030"-.050", or even more but you would need to experiment to find the best jump distance.