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Sawcarver
01-14-2017, 08:29 PM
Good evening,

I am in the process of putting together a F-TR rig for my son and I have run across something odd. The action I am using is a 12FV that has a 308 bolt face. I was going to order a .223 bolt face for it and saw midway had a complete .223 bolt on clearance description said "M10 and M11 .223 short action right hand bolt assembly" so I ordered it, then I can just swap bolts. The bolt showed up I put it in the action (no barrel) and the bolt won't close. Tried it in a few other actions still won't close. If I loosen the bolt assembly screw three turns it will close, or course the bolt handle is loose.

I measured the bare bolt body it is 5.133" I checked two other bolts and two striker bolts and the bodies all measure 5.198-5.202. So do I have a bolt body made to short or am I missing something here?

Thanks

Adam

Robinhood
01-14-2017, 08:50 PM
I get 5.320 OAL on the first one I checked. Starrett 120X

Sawcarver
01-14-2017, 09:11 PM
I didn't measure the tabs for the bolt handle.

Robinhood
01-14-2017, 10:51 PM
I did.

short round
01-15-2017, 01:28 AM
Try a different bolt handle, the new one may be thicker.

J.Baker
01-15-2017, 12:02 PM
Welcome to the wonderful world of Savage!

At the factory they really don't check QC on the parts coming in from outside vendors. Bolt assemblies are assembled separately on their own line, then mated up to an action later on. Essentially an employee at the factory grabs a bolt assembly and puts it into a bare action. If it fits it stays. If it doesn't fit they try another bolt assembly. On the next action in line they try that bolt assembly that didn't fit in the previous action - if it fits it stays, if not they grab another one. If the same bolt is tried in multiple actions (no clue how many) and doesn't fit any of them it gets set aside as a reject. What they do with the rejects from that point is anyone's guess. I would assume someone would tear it down and check each part to see what was off and why it wouldn't fit any actions as that would make the most sense.

That's their QC in a nutshell, which is why often times when you order parts they may or may not work in your particular rifle. One has to remember that there are +/- tolerances on each individual part being sacked up, and if you get an accumulation of parts on a bolt assembly that are all on the + side or all on the - side of tolerance it's quite possible the assembly won't function in an action.

RC20
01-15-2017, 12:22 PM
Some years back we were overhauling a Volvo diesel (I was the assistant)

The more experienced guy was putting in liners and feeding me pistons down the bores and I was getting the connection rods aligned onto the crank shaft and putting the bearing caps on.

We had done 2 or 3 on a 6 cylinder and he said, we have to stop I have to sort this out.

I came around and he had Pistons that were labeled A and C. and liners B and D. Huh.

When we finally got it sorted out with a lot of measuring and trying to figure out what the book was saying, hey had A pistons that were Oversized and liners that were undersized (too big a hole)

They had pistons that were too small and liners that were oversized.

Rather than come up with a quality control program that had all pistons within a normal spec and the liners to a match spec, they just measured them and sorted them so they had the spec clearance. No idea what they did with any that were even further off but apparently pitched them as there were no other letters used.

Then to confuse things they matched those up with letters with A piston with a D liner.

Hard to get out of the manual as the translation was weird and you had to know what they were saying (or sort it out the way we did and then back compare it to the book procedure and explanation )

Never saw that before or since. Unique to Volvo.

Robinhood
01-15-2017, 03:07 PM
What is the length from the lug abutments to the back of the action?

sharpshooter
01-16-2017, 03:09 PM
You have a short bolt body. Nominal length should be 5.200".

Sawcarver
01-16-2017, 09:39 PM
Robinhood measuring the entire bolt body I get 5.247" and from the lug abutment to the back of the action on my receiver is 4.900"

Sharpshooter, that's what I was pretty sure of, I will see what midway wants to do with it. Thanks everyone

sharpshooter
01-16-2017, 10:05 PM
You are better off just changing out the bolt head. The bolt heads are the most consistent component of the entire assembly.