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Lbass
12-10-2016, 01:15 PM
I'll give the parts list first:
Stevens 200 Long action
PT&G bottom metal
AICS 10rd, 300WM magazine modified
Stock Trigger
Thicker Recoil Lug
Stock Barrel Nut
Choate Tactical Stock
Swapped bolt head and corresponding parts to WSM
Larger bolt knob
Harrell Muzzle brake
EGW 20MOA base
Vortex 30mm Rings
Vortex Viper 6.5x20x44
X-caliber barrel chambered in 7WSM throated for 195gr Berger EOLs in 1-8 twist.

I've been gathering parts for this build since Berger announced the upcoming bullet in fall of 2012. Pretty excited to get it going. Since it was so cold outside Thursday that I didn't want to work outside, I finally screwed this project together, and everything looked good except for the poor milling job on the bottom metal.

Took it out Friday for a bore sight and test fire with factory ammo. First round went off with no evidence of a problem. The bolt cammed open easily but wouldn't pull back. I gave it some time to cool down. Eventually tapped it open with a mallet. No visible gouges or bulging in the case. Checked headspace again. The fired brass won't go back into the chamber. I don't mean it won't cam shut. It looks like the bolt stops the length of the neck short from closing.

Still feeds and extracts unfired ammo flawlessly.

Any ideas? I'm thinking the chamber neck is to tight and I need to send the barrel back to the smith.

Thanks, Lonnie

RC20
12-10-2016, 01:48 PM
Some thought on over pressure.

What powder and what load?

Small barrel nut? (I knew little about Steven)

Reports of the Short magnums not playing happily with the small nut setups.

Are you using a head space gauge or a shell?

What is the COL of the cases?

Lbass
12-10-2016, 02:22 PM
Federal Fusion 150gr from Cabelas. I don't test fire with handloads if I can help it.
Small Barrel nut
Using Gauges.
I haven't checked the COL, It really doesn't mean much when you have already changed the mag and throat dimensions. At least I wouldn't think so... but I'm not handloading for it until the bugs are worked out.

RC20
12-10-2016, 04:47 PM
My apologies, you did say factory ammo and I was reading the Berger and did not catch.

I will have to chew on it, its not making a lot of sense. If the rounds go in freely and no squeeze, then it tend to over pressure indicator.
i.e. it seems it has room to expand.

Frankly what I think I would do is load up 3 rounds low level starting loads and see how they do.

Using a shell holder to check to see if the cases slide in and out freely is one of the pressure indicators.

Measuring the brass if you have a micrometer is another.

One of the group tricks is to insert a shim between the rear baffle and the receiver before you open the bolt and see if that extracts it.

Sometimes called PE here ( Primary Extracting) issue though my personal view is the its PEF ( Primary Extraction failure) that has other causes.

I would use brass that is trimmed to minimum length for the test.

short round
12-10-2016, 05:02 PM
Call X-caliber & get neck dia. specs , measure loaded round neck dia. Loaded round should be smaller by.002" or a little more.

Lbass
12-10-2016, 06:24 PM
Call X-caliber & get neck dia. specs , measure loaded round neck dia. Loaded round should be smaller by.002" or a little more.

Loaded round neck diameter is .3115-.312
Fired round is..318
I'm not sure what the standard expansion should be but a fresh bullet will slide freely through the neck.

Work was done by Jim at Apache. Havent got in touch yet.

Thinking it may be tooling marks with the throating reamer, but i haven't pulled the gun apart yet.

RC20
12-10-2016, 07:55 PM
I would think marks would be on cases.

I have had Savage barrel chambers get sticky after 30 or 40 rounds, sure not with the XC I have (nor the Shilen)

Ergo the thought on expansion of the neck/ Shoulder into a too short chamber. I have been able to duplicate that with brass fired in other gun.

That's whey I am suggesting trimming some cases down to minimum or even sub minimum by 5 or 10 and see what happens with a low power reload.

Resized cases checked to be sure they go into the chamber and back out fine before you load them.

I am not big on that as there is a lot of extraction distance in the baffle but its possible.

We need more than one sub set data wise, get as much data as you can before you take the barrel off. .

Take a shim with you when you go to shoo the trial loads.

the other thing I do keep in the car is a small brass rod to tap out problem cases but a bit of tapping on the handles is not going to hurt.

You changed a lot around so it could be with tolerance that the extraction is not enough, ergo the shim.

drybean
12-10-2016, 08:25 PM
Will a bullet fit in a fired case, if not the neck my be to tight on the barrel

short round
12-10-2016, 08:59 PM
Neck dia. looks good. I suggested .002, as minimum & you have .006. Neck size only piece of brass & see if it will chamber. If it chambers, it's time to check primary extraction. Possible that the ammo, is on the hot side for this barrel, try mild reload, to test, if good, work up load.

1953greg
12-10-2016, 09:25 PM
best i can remember most all my extraction issues are because too little headspace. maybe try putting one layer of masking tape on loaded case head and see if it will chamber. if it wont then headspace is too tight

Lbass
12-10-2016, 09:50 PM
Neck dia. looks good. I suggested .002, as minimum & you have .006. Neck size only piece of brass & see if it will chamber. If it chambers, it's time to check primary extraction. Possible that the ammo, is on the hot side for this barrel, try mild reload, to test, if good, work up load.

Tried a new empty brass, chambered fine so I fired a primer off. Didn't expect that to cause enough pressure to change anything, but it couldn't hurt.

Neck sized the real fired brass (not the primer fired brass), it chambered but it got hard to move right before camming it shut. Cammed closed and open fine, had to hit it with my palm to slide bolt back.
Brass after neck sizing measured .309-.310. Seems like a fair amount for tension.

Went ahead and full length sized as far as the die would allow and it still looks like the shoulder didn't move. But I can't find my magic marker or a way to smoke the neck so it's hard to tell. Confusing either way as it still doesn't chamber like a fresh piece.

I won't take the barrel off then as long as you guys think i'm safe to fire a few of the low powered loads, but it will have to wait until Tuesday when I'm off work.

RC20, I'm not sure I'm following with the shim. My mind jumped to a feeler guage between the bolt body and baffle, but with the floating bolt head... It's not working in my mind. Do you mean an extra crush washer?

Drybean, yes a new bullet will slide freely.

RustyShackle
12-10-2016, 10:01 PM
What he's referring to is Primary Extraction. A search for that will pull up the information you are wanting.

When you open the bolt handle does the handle make contact with the rear baffle forcing the bolt to travel rearward in the action?

http://www.savageshooters.com/content.php?281-Why-110-Series-and-Axis-Bolt-Handles-are-NOT-Interchangeable&new_comment

Lbass
12-10-2016, 10:03 PM
best i can remember most all my extraction issues are because too little headspace. maybe try putting one layer of masking tape on loaded case head and see if it will chamber. if it wont then headspace is too tight

I put a piece of scotch tape on a round from the same box, chambered.
I put another pc on the go gauge and it was tough to close.
If I remember right, Scotch tape is .0025-.003... To thin to get a good read with the calipers I have at home, but I've checked in the past.

Lbass
12-10-2016, 10:14 PM
What he's referring to is Primary Extraction. A search for that will pull up the information you are wanting.

When you open the bolt handle does the handle make contact with the rear baffle forcing the bolt to travel rearward in the action?

http://www.savageshooters.com/content.php?281-Why-110-Series-and-Axis-Bolt-Handles-are-NOT-Interchangeable&new_comment

That article cleared that up for me. The ramps on the handle and baffle are lining up. I couldn't get a measurment on the back baffle so I checked where the front baffle was at the beginning and end of opening the action. looks like ~.075 travel.

Lbass
12-10-2016, 10:15 PM
You guys have came up with more solid ideas than I could have hoped for, and I do appreciate that.

RC20
12-11-2016, 04:34 PM
You are welcome, that is what we are all here for, to help as much as we can. We also disagree at times so there is a sorting process.

My mantras is: Follow the Data. If the Data Does not Fit the theory, come up with a different theory.

So yes you can put a shim (feeler gauges) between the baffle and the receiver and get MORE extraction distance
I will say there is a raging disagreement on what is called a PE issue (possible) and what I call a PEF aspect.
Doing the shim overcomes an issue, but in many cases I don't think it is treating a symptom not an underlying cause.

Sometimes treating a symptom is a better less costly solution that an underlying cause.

I think yours is a PEF. From your description, your case neck is expanding enough to move into interferes with the chamber.

I think the next move is to put a piece of Freeze Tape (thicker) on the go gauge, reset the headspace so that it closes easily on the GO gauge with that tape on it.

That may clear it up. Easily proven with the next shot.

Lbass
12-16-2016, 11:35 AM
I went ahead on my last set of days off and loaded a reduced power round. Same problem, every bit as bad.
If I stand the gun up and drop the case down in the chamber. I can push on the bolt hard enough that you can hear the extractor click over the case head, then measure from the back of the front baffle to the front of the receiver cutout as they are flush when the chamber is closed.
It measures .240-.245... The same length as the case neck, if that helps any.

I'm going to pull the barrel this weekend and check protrusion with the go-gauge, clean it real good again, maybe use a friends bore-scope.
Then I'll reset the headspace with some packing tape on the go-gauge, that's a bit thicker than scotch tape.

Where see where that leaves it.

Thanks, Lonnie

RC20
12-16-2016, 11:50 AM
I think that's the right move. I went and re-read you first post, what got me is you said it looked ot hit the mouth of the case and would go no further.

That indicates its not a head space problem, its a throat problem.

Supposedly the brass should fire form to the chamber including the throat area.

If it was head space then it would go almost all the way in and stick.

I would focus on that area, even if tight, a resized round goes in, should conform.

Really odd an most interested in what you find.

Boro scope is going to be the only thing you can get a good look at it with as that is close to the lands.

Robinhood
12-16-2016, 06:29 PM
Something the master Savage Smith has said before is that the reason Savage uses a large shank for a WSM is extraction issues with small shank barrel. May be an expansion and contraction issue.

keeki
12-16-2016, 07:00 PM
I'm having the same problem with a x caliber barrel in 25/300 wsm. I've got new brass coming and I'm gonna figure this out