Quick 308 question

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Freerider

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Been loading for a year now I load for two different 308 rifles one I shoot 175 SMK the other I decided to try 155 SMK. Did all my case prep went to seat the bullets and no resistance when I seated totally different from others I've seated neck tension is so low I can push the bullets deeper in the case with my finger using the same lee collet neck sizer throughout. Been scratching my head trying to figure out the cause then I measured the dia of the bullets just above the boat tail the 155s are measuring .306 my 175s measure .307.5 is this common? Reason I am concerned is the 155s were going to be for my M14 low neck tension would be a bad thing is this common for this bullet weight or did I just get a bad batch? Hope not was looking forward to using this bullet.

Thanks
 
Might be my calipers got a decent set of digital they've been bang on till now checked zero before measuring and even if their off the 155s are still .001 smaller run then the 175s strikes me as strange.
 
Seems like you have a bad bunch of bullets. About the only way to salvage the situation that I know of is to use the Lee factory crimp die on your loaded rounds. they will then be reliable, but probably not as accurate as properly sized bullets. Or pull them all and start over with different bullets.
 
My micrometer is not super accurate but you got me wondering so I did some measuring.
Nosler Custom Competition product code 53169, every 155 bullet miked .3075
-Lapua Scenars in 155: .308,
-Lapua Lockbase, 170: .308
-Sierra Palma Match 155 #2155, .308

What gives? Noslers are 'out of spec?'
 
I've measured bullets for a .243 to be from as low as 0.2426" (Sierra) to 0.2428". Flat base bullets typically have a pressure ring at the base that is a bit larger than nominal -- 0.2432 or so.

But, 0.306 in a .308 is too small, and would not work with your Lee Collet die. If the number is accurate, and I would assume it is if your bullets fall into the case, then you must have a bad batch of bullets. Call Sierra to see what they say.

Also you can buy a micrometer that reads to the 1/10th of a thou for as little as $20 at a place like Princess Auto. Worth getting one for reloading.
 
I have a lee factory crimp die used a light crimp on these they shoot ok not as well as expected but ok. I wouldn't describe them as falling into the case if I set them on the table it takes quite a bit of force pushing down with my thumb but I can make them move biggest thing I noticed was the lack of force required to seat them with the press. I did have a few where when I placed them in the case they felt lose and was literally able without alot of force to seat them with my thumb. Should of just pulled them and tried to return them. Unfortunately I didn't think to check the bullets until after I fired 20 of them.
 
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