Help with very difficult extraction

[rfurman24]

I bought it, shipped it to Fred and he timed and trued it and installed the barrel.

[rfurman24]

Okay, Bill, The tape did nothing. But since you though it was PE I used a .025 feeler gauge and stuck it between the rear baffle and the action. With a fired case bolt lift is very difficult but the bolt actually slides open with ease.

[rfurman24]

A different bolt did not help

[BillPa]

A different bolt did not help


Yeah, and it may or not, its why Fred says sure they'll probably fit, but not be right.

"I used a .025 feeler gauge and stuck it between the rear baffle and the action. With a fired case bolt lift is very difficult but the bolt actually slides open with ease."

OK, the initial bolt lift is one thing, the extraction is another.

One thing with the .025". Did it cycle normally without a cartridge and the .025 shim? What I'm looking for is too much PE with the shim, the lugs and PE cam are engaged at the same time. What you'll see if that happens is some resistance the last bit of bolt rotation at the top and/or some hard resistance closing the bolt.. You could try a bit more shim, but try cycling the action without a cartridge just to make sure you didn't go too much.

As far as the bolt lift is concerned that can be a number of things. Lets get the bugger pop'n the brass out then toss some ideas around to address that.

Bill

[rfurman24]

I cycles fine with no cartridge and the .025 feeler. As a matter of fact little to no pressure is put on the feeler with no cartridge. I took the barrel off, inspected everything(I found no problems), and reassembled(resetting headspace). Still no luck. I think is going to have to go back to Fred.

[BillPa]

I cycles fine with no cartridge and the .025 feeler. As a matter of fact little to no pressure is put on the feeler with no cartridge. I took the barrel off, inspected everything(I found no problems), and reassembled(resetting headspace). Still no luck. I think is going to have to go back to Fred.



Hummm.......050"+ .025" = .075"...thats about right..

If you want to measure the amount PE, pull the barrel, close and lock the bolt then take a measurement from the receiver face to the bolt head. Next, unlock the bolt, but keep it pushed fully forward then take a second measurement. The difference between the two is the PE. BTW...Make sure the bolt handle isn't making contact with the sides of the notch in the receiver when the bolt is closed.

Was the bolt handle changed out with a custom per chance? Any other parts changed out?

Bill

[PEI Rob]

Sounds like the chamber is too tight to me. You say Fred installed a new barrel, was it a pre-fit? They are likely chambered from the barrel maker not Fred. Add as much shim as you can with an empty chamber and still have a functioning rifle. Fire a round and use that shim, it should come out easily. If not, the chamber is too tight. A sized case works fine right?

[rfurman24]

I am not understanding what you want me to shim. I still has a little more effort required to open the bolt on a sized case than I think it should. Even though it is t&td it is a little more difficult than my other savages. After talking to Fred today I think the chamber is too tight as well.

[hershey]

have you tried lube on the case, my ar-10 is very tight on extraction but a touch of gun oil or lube on the unfired round keeps it running nicely. kinda leaning towards that polishing suggestion, but the lube will tell you if your going in the right direction w/ that suggestion.

[BillPa]

I am not understanding what you want me to shim. I still has a little more effort required to open the bolt on a sized case than I think it should. Even though it is t&td it is a little more difficult than my other savages. After talking to Fred today I think the chamber is too tight as well.


Like I said before, extraction and bolt lift are two different animals.


I used a .025 feeler gauge and stuck it between the rear baffle and the action. With a fired case bolt lift is very difficult but the bolt actually slides open with ease.

If the bolt slides open with ease it means for what ever reason the PE is on the short side. Why, I don't know, you'll have it checked and corrected.

The hard lift could be caused by a number of things and without having the rifle in hand all you, I and everyone else is doing nothing but looking over the Chinese menu of fixes. So, at this point i suggest sending the barreled action and a few pieces of fired brass to Fred for his "look see".

Bill

[rfurman24]

I agree Bill. I think as I stated before it will have to go back.

[AKArcherdaddy]

I'm not nearly the expert that some of the others helping you out are, but I have one piece of personal experience to add, based upon your description of difficult extraction and ruined cases. Not sure if it even relates, but maybe.

I had a PAC-NOR 257 Wby barrel built for my 116. I broke it in with about 50 rounds (and frequent cleaning) and then started developing loads. About the 3rd reloading of my brass I began having similar issues: proven mild loads would show serious pressure signs and be very tough to extract. My chronograph also began to read ridiculous speeds, but widely varied.

Long story short, the necks on my brass had grown too long and this was "squeezing" the bullet too tight in the chamber before firing. After ruining several cases, blowing some primers, all the while backing further and further down on powder, I figured it out, trimmed the brass, and everything went back to normal. Could it be that maybe your brass is too long, or the neck in your chamber is too narrow for the brass you are using? This theory is further supported by the fact that you say it's difficult to fit a bullet into a fired case. It sounds like your chamber neck may be so tight that there isn't enough room for the brass to release the bullet properly, hence causing pressure problems, and hence ruined brass and difficult bolt lift and extraction.

Just a thought.

[rfurman24]

I will not guarantee that is not the problem but I am trimming the brass well on the short side and have measured neck thickness as well as neck size of fired cases and all are in specs.