Help diagnosing hard bolt lift-6.5x47 Remage

[AKShooter]

Hello

Have an odd issue I thought I'd put out there. Looking for a different image hoster too, seeing photobucket now wants to be paid

Build
Stiller Tac 30. Remage system. 6.5x47.

Working up a 130 Berger with H4350 and varget.

Issue is I'm getting a sticky bolt with powder charge close to but under max per Hodgtons site. But it's odd. Not really seeing the normal pressure signs. No extractor marks. Seems just on case just outside of primer. I'm also getting a ton of brass on face of bolt. 50 rounds out of barrel. Slight cratering on primer but not bad. Worse with Varget, started getting sticky bolt at 35.5 grains with the 130

So, what I've tried. In regards to the sizing the fired rounds. Redding FL bushing die. It will size fine. Cases chamber fine.

I also picked up a Redding bushing neck sizer too. These extract hard. Extraction almost matches post firing. Die set for a decent cam over. Chambering these rounds leaves excessive brass on face of bolt.

I did notice the extractor was very stiff. I have cut a few coils off, and polished the extractor itself. Much better.

So, maybe I'm just pressuring out,,,,certainly can be the case.

Another thought I had, and one I'm going to fix. I chambered it myself, I've done quite a few of these. What I did notice, I definitely have some drag on the GO gauge. Not much, but its there. It won't even start on a NO GO. Firing pin and extractor were removed for the tests. Thinking maybe I've created too tight of a chamber?

Thoughts? I know I need a bit more range time, run some speeds, etc.

 

[Alex Wheeler]

What is the chamber finish like? Does it look coarse?

 

[AKShooter]

I'm pulling the barrel and resetting tomorrow. But with a light it has a pretty good shine.

 

[gotcha]

I'm pulling the barrel and resetting tomorrow. But with a light it has a pretty good shine.

I think Alex is trying to say it may be too slick. .............. Measure your go-gauge then measure fired brass. Your fired brass & your neck sized brass will probably be longer than go-gauge indicating the chamber walls are too "slick". ................... Your neck sized brass is leaving brass on the bolt face because you haven't bumped the shoulder back. ....... You'll need a machinist dude to tell you how best to make the chamber more 'grabby" without changing chamber dimensions.................. The build up of brass on the bolt face is just making the situation worse. Just my .02 BTW how much bump are you putting on cases with the F/L die?

 

[AKShooter]

That's where I figured Alex was going to. But not speaking for him. But certainly don't mind using some wet-dry to get a bit more grab. I'm do some research, or Alex, if you are still following this, have any recommendations? On the bump, need to get a comparator for this, I'll go at lunch. But only way the full size chamber is with a hard cam on the re-size. But current plan is to:

1. Re-set the barrel so the bolt drops freely on the GO (sometimes when torqueing nut you can turn barrel, think that's what happened) And of course check it against the NO-GO. But get rid of the drag,,,,I think this is at least contributing to it.

2. Re-test fired brass, against "new" headspace.

3. With either new or re-sized brass repeat load testing. Ensure chamber and cases are clean.

4. Possibly scuff chamber area before re-setting barrel.

Thanks for the responses, with quality components, and Hodgton's data (which is fairly conservative IMO) I've never had any issues reaching their published max. This one has me confused, thought I'd ask here. Lot of knowledge here. My wife and I are expecting our first child any day, but will certainly update post as I get results back.

 

[Ledd Slinger]

Technically speaking it's your 'ejector' plunger that will leave marks, not the exctractor.

Do the loaded rounds chamber smoothly?

Take your ejector plunger and spring completely out of the bolt face and fire a couple rounds. If still sticky, try backing the load off a full grain to see if it makes a difference.

Could also have a barrel with a tight bore that is causing the round to reach max pressure with lesser charges of powder.

Another kind of dumb suggestion is to also make sure your cases are trimmed to proper length.

 

[gotcha]

LOL, I can't help you with wife's up coming contractions since there is nothing on the subject in the Sierra manual. If you have a spare shell holder try polishing about .0015" to .002" off the top. Flat surface, figure 8 movement with 400 grit wet-or-dry. this will allow sizing without all that cam over. Just another way to skin the case sizing cat. ........ I'd agree with your desire to re-set H/S. Lay a piece of tape across the barrel nut and receiver to check for movement during barrel nut tightening or scribe witness marks on bottom of receiver (out of site when stock is in place) It doesn't take Gorilla tight to lock your barrel in position. I just hit the BBL. wrench a good slap with the palm of my hand. NO CHEATER BARS !!! Here's hoping that baby is happy and healthy

 

[AKShooter]

Thanks! Okay, just realized I can drag and drop an image, so here it goes.

Right to left, bolt head, started as a clean face. Brass deposits are from cycling neck sized case in the middle 4-5 times. I was getting more than this after firing 20 or so.

Next is a fired case, still showing the brass wipe, just slight primer crater. Middle is the neck sized case. Lastly a full sized and chambered case.

 

[fastnflat1]

Has it been verified that the bolt face is perpendicular to the axis of the bolt body/chamber? looking at the pic i see heavier depositing on the right hand half of the bolt face (imaginary line from 11 o'clock to 5 o'clock)

 

[noload]

You need a shoulder bump comparator to be sure you have enough bump. Measure your brass (diameters of shoulder and base of cases) after firing and after sizing, that should give you an idea of whats going on.

 

[Milo 2.0]

I'm going to go out on a limb and say your die is not constricting the base area of your case enough, measure around where the die ring is on the brass.

 

[Alex Wheeler]

Too coarse is more of a problem than too smooth contrary to popular belief. You want bolt thrust use some 180 and you will have plenty.

 

[Zero333]

From the pic I see a ejector moon imprint (half moon in this case) under/besides the "A".

Regardless of what any manual says the Max is, your rifle is saying otherwise.

Drop the charge weight down. You could still be getting max velocity at a lower than max load.

 

[Ledd Slinger]

I think it's something as simple as what Zero333 stated. The rifle is reaching max pressures at lesser charge weights than what is listed in the books.

What is the barrel length and bullet speed?
Was there non-linear speed gains after the last charge weight increse during load development? (Less speed gain with last increase)
A chronograph can give you wealth of information to determine if max pressures are being reached or exceeded.

Characteristics of a fired primer are not guaranteed to show you signs of max pressures.

 

[gotcha]

Your 4 step plan is just what is needed. Get the H/S issue under control and the other problems will probably go away. I had the same issue with my 6.5X 47L. I'm a bit lazy so I shortened the shell holder to the point that I got .002" H/S with the F/L die set firmly to the shell holder. Do one 4 step operation at a time and check results........ You don't need a special H/S tool. A .357 pistol case with primer removed and a caliper will allow you to locate the mouth of the case on the shoulder of the 6.5X 47L and give you accurate comparative readings. Any cylindrical object that is squared will also do.

 

[AKShooter]

Thanks for all the replies. As an update, actually added another step. I had another brand new stiller action in the safe. I pulled the barrel and was resetting headspace on the old one. I never could really get the "drag" out of the bolt on the GO until it would close on the NO-GO. This action was used, and you can see a pretty good wear, maybe galling on the receiver lug face. It also looks like I'm not getting much contact on the other lug. I'm going to send it out to a smith to access. I remember seeing it when I bought it, didn't give it much thought. Action cycles pretty hard too,,,and it was greased


But, barrel spun up perfect on the second action. bolt falls freely on the go. NO-GO, bolt just starts to close, maybe 1/4-inch. We will repeat the process LOL Fired, neck sized cases chamber. But I'll start this next panel with new brass. Get some tools to measure setback, and run it over a chrono

 

[gotcha]

Thanks for all the replies. This action was used, and you can see a pretty good wear, maybe galling on the receiver lug face. It also looks like I'm not getting much contact on the other lug.

Seems like this might explain Fastnflat's observation about the half moon brass deposit on the bolt face Lugs & lug shelf appear to need truing on the original action you tried to head space. ....... Lucky you had another action to test

 

[Uthink Uknow]

Why are you using the Rem/Age system?

Also: What is ejection like? Is the spent case really flung out or does it just clear the action?

 

[carlsbad]

The manson lug truing tool is very effective in truing the lugs in the action if bushings are fit correctly. You can then adjust your headspace. however, this will affect your extraction timing and ignitiion timing so those should be adjusted, especially if your load is on the hot side.

--Jerry