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brazos river
09-07-2020, 09:20 PM
I have a savage model 10 in 308 win. I have been have some real good groups with 180 gn sst's. I have started to get heavy bolt lift and I had to replace the ejector spring. I am now getting some failure to fire looks to be light strikes on the primer. The load I am using is 44.5 gn of varget. could this load be putting excessive wear on my bolt. I would not think so maybe the parts just need replacing. thanks.

sharpshooter
09-07-2020, 10:17 PM
It would seem that your loads are too hot and jamming the ejector. This would lead me to believe you have also blanked a primer. The slug from the primer is lodged in the bolt head and prevents the firing pin from reaching the primer and also kills the inertia.

charlie b
09-08-2020, 07:50 AM
Hodgdon lists a min load of 44.0gn and a max load of 47.0gn, but, I have found their loads to be on the warm side. Are your primers flattened, cratered or pierced? How many rounds have you fired through the rifle? Do you full length size or to you set the die to just touch the shoulder..

If the rifle is fairly new it may be just that some grit has worked into the bolt and needs to be cleaned out. I'd also clean the chamber well.

brazos river
09-08-2020, 09:04 AM
I purchased the rifle used so I don't know how many rounds have been shot out of it. I have shot full length and used the lee collect die for neck sizing only neck size only is a bit more difficult to open. the primers seem flattened the feel smooth as run your finger across. Once I figure out how to post a pic I will add it.
thanks for the replies. The case with the marker was neck sized.

https://s765.photobucket.com/user/redriverhunter/media/full%20sized.jpg.html?sort=3&o=2https://s765.photobucket.com/user/redriverhunter/media/full%20sized.jpg.html?sort=3&o=2https://s765.photobucket.com/user/redriverhunter/media/neck%20size.jpg.html?sort=3&o=0https://s765.photobucket.com/user/redriverhunter/media/neck%20size.jpg.html?sort=3&o=0

https://s765.photobucket.com/user/redriverhunter/media/full%20sized.jpg.html?sort=3&o=2 (https://s765.photobucket.com/user/redriverhunter/media/full%20sized.jpg.html?sort=3&o=2)

wbm
09-08-2020, 09:13 AM
This is the online Hodgdon data for the .308 Winchester

Barrel 24" 1-12

180gr Speer SP 2.80" OAL

Hodgdon Varget
41.0 2,470 2470fps 41,200CUP
45.0 2,661 2661fps 49,600CUP

tobnpr
09-08-2020, 09:45 AM
Back up a bit and provide some more context/history.
New rifle?
44.5 of Varget under 180's wouldn't usually cause overpressure signs. Is this problem taking place during load development, or was that long ago but you're just having the problem manifest now?
Trying to figure out the replacement of the ejector spring and the timing/reasons behind it.

Light primer strikes and hard bolt lift are difficult to tie together, more info would help.

brazos river
09-08-2020, 01:04 PM
I purchased the rifle used. I did a I believed it called ladder test stared a min and worked up at 05 gn. I the problem started after I had settled on 44.5 gn I loaded up 5 rounds and see how they grouped they grouped great. but the bolt was a bit sticky and had minor ejection problems. replaced the extractor and the ejector spring and ejector (old spring was dead) it now works great. Before I take it back out I will give the chamber a good cleaning I have another savage in 308 I may take the firing pin assembly out and see if it will work.

charlie b
09-08-2020, 04:36 PM
wbm, Thanks for the correction on the Hodgdon data. Don't know where I screwed up the data.

Hodgdon usually lists 'warmer' loads. I am usually a full grain below the max with their data when I start to see flattened primers and hard to extract cases. For example, I run 43.5gn Varget with 168gn AMax and SMK's that gives me 2750fps. Hodgdon shows 45gn gets same velocity.

brazos, you might try backing off the load a bit as well. Especially if you can't run it over a chronograph to see what your rifle is really doing.

Robinhood
09-08-2020, 05:29 PM
I would use no more than 44 in a Lake City or Lapua brass. The SST has a long bearing surface doesn't it?