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Discussion Starter #1
I don't know what was going through my head when I was reloading 308 for my 17s, but I clearly read COL from the manual of 2.775". When I seated the bullets I did it to 2.755". The powder charge is the low suggested start (40 gr of IMR 4064). I think 2.755 is still in tolerance of 7.62/308 so I'm tempted to use them. Would you pull the bullets and re-seat to 2.775"?
 

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Funny you should mention using IMR4064 as I just purchased 8lbs of it for my 7.62X51 loads.

Where exactly are you on the "low" suggested powder and what projectiles are you using? You must be using the Lyman data with a 168gr projectile for 40 grains of 4064 powder. If this is the case, I think that you should be OK for .020 shorter seating depth however, it is entirely up to you and whether you want to risk your firearm. Considering this is the start load (if my assumption is correct) data, I would check the first fired case for any signs of overpressure.

As a precaution, call the powder manufacturer or projectile manufacturer for a clear and concise answer to your question.

Are you using MIL or standard brass?
 

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Discussion Starter #3
Spot on. I'm using 168 gr SMK data from Lyman's 49th. It's standard brass I recovered from a box of PMC Bronze I took to the range.
 

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I think you should be OK but I still would call either the powder or projectile manufacturer for their input. I know that it seem like a pain in the arse to do it but it is only a couple of minutes of your time for some verification. I have never used the IMR powder before so I will be working up some load data for both my SCAR17 and Remington SPS 700 with some 149gr M80 ball and 175gr Sierra Match HPBT (M118LR equiv).
 

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Discussion Starter #5
I caught myself after 10 loads and readjusted to 2.775 for the 2nd 10. I shot them last weekend. Not bad at all. Cycled the 17s perfectly. Accurate enough for the plinking I was doing. I don't have a chrono so I have no idea about velocity. My only issue with IMR 4064 is that it doesn't meter very well.
 

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IMR 8208XBR is phenomenal in a shorter barrel gas gun and burns like IMR 4895 (you can use 4895 data if you use-1grain to start). IMR 4064 is very similar to Varget but less temperature stable. I would always see the velocity keep increasing as the rounds "cooked" in the chamber with 4064 (or any of the less temp stable powders).

Sorry for the derail, just posting my 2 pennies.
 
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