Author Topic: Seating Bullet Depth  (Read 384 times)

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Offline RFD18

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Seating Bullet Depth
« on: January 21, 2011, 02:05:08 PM »
I have a question about seating the bullet just off the rifling.I have just started reloading for a 22-250 with an OAL of 2.350.After checking seating depth I find seating out to 2.44 is just off the rifling.My question is by seating the bullet out more than the OAL,what effect does this have on the pressures.Does it change it by a great deal.



Offline DANNY-L

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Re: Seating Bullet Depth
« Reply #1 on: January 22, 2011, 02:37:13 AM »
I dont know about the pressure but I have always had great accuracy with 2.350 and the 50gr.nosler bt,couple days ago I check my oal until touching and backed of .010 and loaded up 5 rounds and will be checking for accuracy when it warms up a bit. My oal for my 700 is 2.406 -.010=2.396 not a whole lot but I just wanted to check it anyway.

Offline FW Conch

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Re: Seating Bullet Depth
« Reply #2 on: January 22, 2011, 03:25:27 AM »
RFD 18, my BIL had a 22-250 that wouldn't shoot for squat until he started touching the lands, then it became a 5 shoot-"one holer".

Internal ballistics is hocus pockus to all of us but ballistics technicians. Touching the lands "can" increase pressure because the bullet doesn't get a jump. However, moving the bullet forward decreases the load density in the case witch "could" lower the pressure, witch may or may not result in a net gain or loss of pressure?

IMHO, touching the lands is fine as long as we start with minimum starting loads & slowly work up, carefully looking for pressure signs along the way.

Be Safe-Good Luck-Good Shooting-Jim  :)
Jim

Offline necchi

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Re: Seating Bullet Depth
« Reply #3 on: January 22, 2011, 03:57:28 AM »
Well I'm a rookie loader to be answering, but your question opens a can of worms when pushing max loads and different powder types.

 But generally, seating beyond SAMMI Max COAL is OK with regards to pressure spikes until touching or jamming the lands. Once your at or on or in the lands is when funny internal stuff happens.
 I'm loading for factory guns and all have long throats so the closest I've been able to get is .020 off the lands and that's .050 over sammi. I was facing run-out issues with the bullet seating in the case neck when I tried to get closer.
 Good advise above from Conch, if your touching the lands work up SLOW.
found elsewhere

Offline RFD18

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Re: Seating Bullet Depth
« Reply #4 on: January 22, 2011, 02:25:53 PM »
Guys thanks for all your input,I am starting with the standard AOL and will work with that for a bit to try and get a good powder charge .Will be starting with H380 working up a few 10ths at a time.