29 October 2007, 21:17
dirklawyerRuger 375 bolt diameter,etc
What is the bolt face diameter on the new Ruger 375? Is the COL 3.6? Thanks
30 October 2007, 01:33
dirklawyerJeff, the .532 is the head size? So the bolt face size is .700?
30 October 2007, 03:20
RIPDirklawyer:
You are confusing "bolt body diameter" with "bolt face diameter."
Jeffe answered your question correctly, as worded.
Max head and rim of the Ruger are .532". Bolt face will usually be cut 0.002" to 0.005" bigger in diameter than the actual brass rim it fits.
The actual .375 Ruger brass measures about .530" as it comes new from the factory, to be sure it fits easily in all the standard H&H belted and .375 Ruger bolt faces.
IIRC, the Ruger bolt body diameter for the .375 Ruger Hawkeye is indeed .700". I would have to check to make sure.
30 October 2007, 03:29
dirklawyerRip, thanks for the terminology lesson. Dirk
30 October 2007, 03:30
RIPDone. Measures about .695" at the point I measured on a Hawkeye.
The old Ruger M77 bolt body diameter measured 0.694" according to Stuart Otteson in his
THE BOLT ACTION Volume II.
Call them both .700" (bolt body diameter or simply "bolt diameter") as that would be within the manufacturing tolerance to be sure the bolt will work smoothly in the action.
30 October 2007, 03:39
ConRIP,
Timely thread ... where exactly do you measure bolt
body diameter? Here are some numbers I got this morning measuring close to the bolt head lugs, I was in a rush hence the "range" of 0.002"

:
M17 Winchester: 0.690-0.692" ... an Eddystone measured closer to 0.698"
P14 (Remington): 0.695"-0.697"
CZ550 (416Rigby): 0.698"-0.700"
Ruger M77MkII (300WinMag): 0.691-0.693"
M70 (30/06) post-64 PF: 0.690"
Rem700 : 0.695"
I thought the P14's bolt body diameter was larger, hence its "preference" for the biggest calibers. But measuring shows no difference.
Thoughts and or comments?
Cheers...
Con
30 October 2007, 03:45
RIPCon,
The P14 has to do with the locking lug extensions of the bolt face and how they can be used to retain the cartridge rim when the Bolt face recess is all but gone. Enfield expert or pictures would have to be used by me to explain anymore.
You are measuring correctly, I am sure, anywhere excluding the locking lugs in the diameter of the straight cylindrical bolt body. Those minor variations would be expected in any bolt action that was mass produced, and model to model, etc., eh?
30 October 2007, 03:56
ConRIP,

I've got you. I've got pictures of both bolts somewhere here. Looking at my rifles I understand what you mean ... the P14 bolt's "split" lug is radiused and much meatier compared to the evenly tapered lug on the M17's which makes it much thinner close to the boltface.
Is that a good non-technical answer??

Cheers...
Con