New member…Krag 6.5x55

[Ned Butts]

WOW!!!!
That is really chopped!! Too bad there is no stretching that one

[butlersrangers]

'Dave' - By serial number, it appears your 'mismatched' bolt is from a cavalry carbine made in 1899.

The attached photo shows a Norwegian sling attached to a Model 1912 carbine.
The same type of sling would have been used on your carbine.

Your trigger-guard once had an 'eye'-bolt on the left-side at the front.
This served as another attachment point for the sling hook.
It is likely the 'sculpted shape' of your trigger-guard bow, was to provide some clearance for the military sling-hook.

The extra effort you wrote about, when opening the bolt, bears further investigation.

It could be due to burrs, hardened grease, or corrosion, causing resistance to the movements that 'cock' the striker-mechanism as the bolt is opened.

It could be due to galling or 'set-back' of the receiver shoulder, which supports the locking-lug and bears the rearward thrust of the bolt.
Does it happen all the time or just when a cartridge case is involved?
Does it happen with just a 'bare' bolt, (that has the striker-mechanism & extractor removed)?
Pulling the 'bare' bolt to the rear, as it is rotated in the receiver, should allow you to feel if there is a problem with the 'lug-recess'.

[Sunshineboys]

Thanks to Butlersrangers. It only happens after firing a cartridge. I can cycle an empty brass casing or a loaded cartridge with no resistance so it has something to do with a fired case. I have closely checked the spent casings for signs of them catching on something and have looked closely at what is visible but I have not found it yet. There are some marks on the cases but it is difficult to tell. I have thought about spray painting a loaded cartridge, firing it and then checking for signs. Any thoughts would be welcome. I worry that eventually the extractor will fail.
There is no resistance during the opening of the bolt until it is 2/3 through it’s cycle. On that first 2/3 opening of the bolt does the bolt move the spent cartridge case at all?

[FredC]

Another welcome to the KCA.

Just to be clear this lifting the bolt is not from pulling back the firing pin? Letting the firing pin down then opening the bolt with an empty chamber causes no difficulty, correct?

I am not sure if I would paint a cartridge. I think the paint could act like a lubricant and lead to excessive load on the locking lug. Before I would do that, I would look for a cartridge with a little tarnish or a pristine new cartridge and look for a ring or partial ring after firing. The spot that is rubbing is probably on the neck and maybe adjacent to the mouth of the case. I think examining your cases with good light and a magnifying glass should solve your mystery. Since a fired can be reinserted with no issue, the raised spot on the case probably does not go all the way around.

On your last question the case should start to be pulled back real soon in the bolt lift. If the hook on the extractor has excessive clearance that could be a problem. When the bolt opening is stopped is there still some rotation left, when you hammer on the bolt handle with your palm are you still rotating the bolt or only pulling it back?

[Sunshineboys]

Letting the firing pin down and then opening the bolt on an empty chamber is no problem. There is no resistance as I lift the bolt and the front locking lug moves to the free position. It is when the bolt needs to start it’s trip back from the chamber with the fired cartridge that I feel the resistance. I am guessing but I expect that the fired case is hanging up somewhere in the chamber. I worry because so far I have been firing reduced loads. I wonder what would happen if I went to heavier loads. When I experience the trouble is as the cartridge starts it’s trip out of the chamber. I believe the first part of the bolt lift is just turning the locking lug out of battery.
Thanks for the welcome to this board. I really do appreciate this help. Dave

[FredC]

How is the fit of the extractor on the cartridge rim when the bolt it out? I expect .005 to .010 inches is about right.

[butlersrangers]

Initial extraction occurs as the bolt rotates.
Once rotation is complete, it should be easy to draw the bolt to the rear.

Since the resistance is only occurring when extracting a 'fired' cartridge case, I would look for these potential problems:

Chamber irregularities - corrosion or pitting, out-of-round chamber, a 'ringed' area in the chamber or an over-sized chamber.

Brass out of specifications - The extractor-groove not correct depth. (What brand of brass are you using)?

Extractor Claw problem - Burrs, a damaged tip, corrosion, rust or hardened grease, that is interfering with proper movement of the extractor and its claw-tip.
(This could be on the extractor itself, in the extractor-clearance notch cut into the barrel-breech, or the cavities machined into the receiver. The 'claw' needs clearance at the sides and to be free to 'lift upward').

Problems like Excessive head-space or an oversized chamber should be detectable by close scrutiny and measuring of fired Brass.

Rub marks and shiny spots are likely present somewhere on Brass or receiver & bolt parts. Check sear-tip and ejector (which pivot below the bolt in the receiver) for potential 'binding' of Bolt movement.

Clear close-up photos of fired Brass might help ID a problem.

[Sunshineboys]

Well, here goes. The extractor seems to be in good shape and it fits into the rim recess well. Brass is PPU. I am using Lee Dies. The first loads were done with a full length resizing die. The second and third loadings were with a Lee collet die. All of these extracted with that difficulty. I have cleaned the chamber thoroughly with brass brush and bore cleaner. Chamber looks fine but looks can be deceiving. The next time I fire it I will take photos of the position of the bolt when it encounters the sticky part. I will also clean that brass with emery paper before firing it so it will show any marks better. Front lug is just starting it’s rearward travel when the difficulty is encountered.
All the parts of the bolt are serial numbered the same, although different from the receiver, barrel and rear sight which are all the same. More to follow. Dave

I will just add on here. My load is 32 grains of 4831 under a Hornady 140 grain bullet. Not a heavy load. I smoothed the casing out with very fine emery paper and then completely coloured the casing with magic marker. Fired the cartridge. I took a photo of the bolt at the point where it stops and has to be kicked to complete the extraction of the empty case. I then kicked the bolt with my palm and the bolt opened but the extractor let go of the cartridge and the spent casing stayed in the chamber. I then used a metal cleaning rod to drop in from the muzzle and the third time to case came out. There are many fine striations length ways on the casing. Next step? Possibly a trip to the gunsmith? I wonder about winding emery cloth around a bronze cleaning brush to see is that would remove any irregularities?

IMG_0634.jpeg (112.22 KiB) Viewed 8407 times

[FredC]

What Br said. All are potential causes of extraction problems.

I zeroed in on the 2/3 of rotation with little effort then it got stiff. The opening cams are engineered to start pulling the spent case right away. If the bolt is correctly moving rearward then gets very stiff my first thought is defective extractor. Since the bolt is a substitute for the original there is a possibility the cam surfaces are not working together and no rearward motion is happening on the bolt till it is past the cam surfaces. We get used to American Krags with very interchangeable bolts. I have no clue with the European ones.

I have observed conversations on the Practical Machinist forum and making the extraction cam surfaces on the bolt and receiver are some of the more difficult parts of building a bolt and receiver.

Edit,
I just checked my US Krag barreled receiver in the toolbox and the bolt handle is pushed rearward by the cam surface on the bolt at about 1/2 to 2/3 rotation. The bolt cannot move rearward till the locking lug and guide rib clear. The cam surface on the receiver is pretty fast, if it contacts before the rotation stops and is pulling on the case then everything Br mentioned is in play. Carefully examining a new fired case should reveal some clues.

[Sunshineboys]

As a conclusion I believe that the cartridge is just plainly stuck in the chamber after firing. When I lift the bolt handle, as soon as it gets to the point where the bolt exerts pressure on the casing everything stops in it’s tracks. The casing has some lengthways striations but nothing deep or nasty. I do have a stainless steel bore brush which is large enough to scrub the inside of the chamber. I will wait until I hear from others before I take that step.