6.5 Creedmoor OAL question

[TackDriv3r]

GA Precision Crusader 6.5 Creedmoor finally arrived. Ready to work up loads for a ladder test, just noticed the OAL is so long and base to ogive measurements with the 140 Hybrids, 142 Sierra MK and 143 ELD-X measurements are as follows,,, 2.271" for the Hybrid, 2.305" for the 142 SMK, and 2.271" for the ELD-X. I would like to try the 140 Hybrids for now, and I have a few questions about the OAL. Are you guys running the OAL that long? I see that the taper of the bullet is 80 % inside the neck and not sure how much I should seat off the lands. I do prefer that the whole shank of the bullet is seated inside 100% of the neck or more. Does it like a long jump? Going to use H4350. Any advise would be appreciated. Thanks

 

[Chris Few]

I run a SAMMI spec chamber in my rifle with 140gr hybrids. I seat 0.015" off the lands and that measurement is 2.162" CBTO.

 

[DirtySteve]

140 Berger VLD 35.2 grs of IMR4166 at 2.80" C.O.L. Best 5 shot group was .25".
40.5 grs H4350, 142 Nosler ABLR, 2.820” COL grouped .65” for 5 shots.
I shoot a Savage action with a Rock Creek barrel 1 in 8 twist.

 

[dmoran]

@TackDriv3r -

The optimal seating position I myself favor is when the shank of the bullet is about 0.050" ahead of the neck/shoulder junction, and do not care if there is shank/bearing surface extending past the case mouth. Here is a Link to an Excel Workbook that I wrote and call "Cartridge Laboratory" that you may find useful:
http://forum.accurateshooter.com/attachments/cartridge-lab-v2015-xls.974207/

Also, here is a thread link to Excel Worksheets of mine that I have shared with the Forum:
http://forum.accurateshooter.com/threads/excel-worksheets.3891679/

Good Luck
Donovan

 

[TackDriv3r]

Thanks guys, loaded them up for a ladder test, .030" off the lands to fit the mag, I'll see if I find a cluster it likes.