308 Savage 12FVSS Bolt Sticking
Today I shot my Savage 308 model 12FVSS, 26 inch barrel. I was beginning load development for accuracy. I fired a couple of rounds into the dirt behind the target just to get the feel of it since I haven’t had the time to shoot this rifle for about 4 months. Following that I settled in to the prone position and got to work.
I loaded some 168 grain Berger hunting bullets over 43.5 grains of Varget and, for comparison purposes, I had 43.5 grains of RL 15 on another batch. I also had some 175 Bergers, again, with 43.5 of RL 15. My GA Precision AR-10 spits out the 168’s with better accuracy than any rifle I’ve ever fired so I started with the same load, 43.5 of Varget…seemed like a good idea to me.
So here’s the rub here…on about 8 or 10 cartridges (out of 45 cartridges) the bolt was stiff to lift and I had to tap the bolt to the rear to move it back (hand-pulling wouldn’t work). In 6 cases I had to rod the barrel to get the fired brass out of the chamber. The 70ish year old reloading/shooting guru at the range told me that I have a tight chamber and that I was loading too hot for this particular rifle’s chamber. The primers looked like any other primer following me shooting a 308. On the Alliant web site and the Hodgdon web site I am well below the max loads, about the mid range in the listed load data. The chamber and barrel started out pristine clean so I know there was no junk down the tube.
My experience is mostly with black rifles; I am at an entry level of skill and knowledge with bolt guns.
So, is 43.5 of Varget too hot when Hodgden says 46 is the max load? What am I messing up? Obviously I need to know something that I don’t know.
FYI: The RL 15 was just to trial of another powder to see what it’d do…no appreciable difference from the Varget.
I would have a tendancy to agree with the old guy at the range. However I have never seen a tight chambered Savage(doesn't mean it can't happen).
Was this brass previously fired in another chamber? Are all head stamps(brand) the same on ones sticking vs ones not sticking?
The first thing that I would try is loading a batch using brand new brass.
My favorite 308 load is 46 grains of Varget and a 165 grain Hornady Interbond. I am just starting to show some pressure signs with that load. It is also the most accurate load in my son's 700 VTR.
Easy to find out, full length resize the brass and drop the powder charge by 5 grains and fire a couple off.
Give the action and bolt a good cleaning to make sure nothing is causing it to stick as well.
Another thought from the old days: measure your cartridge case with those loads fired in the Savage.
Lyman, Hornady, Nosler, Speer, Barnes, Sierra, and Hodgdon manuals indicate that case head expansion should be measured with a blade micrometer (so you get a reading at exactly the same point on a marked case head) on once fired or twice fired brass, and should stay below .0005" to maintain safe pressure. Several books recommend range of .0003-.0004" as a maximum useful expansion. .0005" approaches or exceeds a very thin safety margin.
Ken Waters was an advocate of this system, I am not sure if the method remains in favor. I load for gas guns mostly, and use THE load for the most part. Hope that helps. Would be interesting to see you data.
Careful tapping on the Savage bolt, handles break, even with a leather mallet. Yes, I did it, after sticking a case, cast bullet load(!).
Could also be a rough chamber finish that needs polished, I've had that on 2 308s, a Browning BLR and a Remington 700. The BLR levers lack of leverage at the very start of opening combined with 308 pressures and a rough chamber wall made it almost imposable to open sometimes but after polishing it runs fine.
I have to admit that I'm not sure what you are talking about. Where do I measure on the case? Is this from the outside diameter of the case head from brand new unfired brass then compare it with post fired base? And if it is > .0005 is this a loading pressure issue or a chamber issue? As for tapping on the bolt...I'd prefer not to if I can avoid it. Oh and another thing...is there a case neck expansion issue I need to learn about or is this not an area of concern.
Originally Posted by allen-ak
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