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Old April 2, 2007, 10:21 PM   #1
straightpull
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Tikka 91/30 Chambering Problem

I have a Tikka 91/30 that wouldn't close on a round. The action cycles okay empty but won't close when I chambered my ammos and empty shells (full-sized). The chamber is clean. I tried different bolt sets and none would make it chamber a round. Then I ground the butt of a dummy ammo to make it thinner, down to where there is no more bevel in the rim. I tried different bolts again and one was able to close with a little difficulty. I believe this is a headspace issue, but I'm not well-versed on this. Should I trim the bolt face it until it operates smoothly? I need help. Thanks.
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Old April 3, 2007, 10:14 AM   #2
Harry Bonar
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tika

Sir:
I don't understand what you mean by "different bolt sets."
Is this a new rifle - what cartridge is it chambered for - where are you getting your "bolts" from.
Tika is a fine rifle and the cartridge is marked on the bbl! Get some factory ammo of that kind and it should work fine. I don't understand what you are doing. This could be a used rifle someone has changed the bolt on, or re-chambered for a different round!
If you will be so kind give us some more information and we'll try to help - DO NOT do anything to the bolt - this is a serious safety issue - be sure to get back with us on this.
Harry B.
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Old April 4, 2007, 12:49 PM   #3
straightpull
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Tikka 91/30

Thank you for the reply. The rifle is not new. It is a military surplus. I'm not sure if you are familiar with Russian rifle model 1891. I'm still learning about it but here is what I know. 91/30 is based on that model and they are chambered in 7.62x54R (rimmed cartridge). They are popularly referred to as Mosin-Nagant - cheap rifles made in the millions. Anyway, this Tikka is my second Finnish-made 91/30 and it has round receiver. My other one has an octagonal receiver made by New England Westinghouse. They are now part of my Finnish-made bolt action rifles in 7.62x54r of which most are M-39 from Sako and Tikka. Since they are all of Russian 1891 action design, bolts are interchangeable (usually). The bolt-head, which has the twin locking lugs, is removable and can be kept or swapped depending on need. Now, on this Tikka rifle I have issue with I can drop the 7.62x54r cartridge in the chamber and it fits as good as in the other ones I have. The cartridge is easily removed by pointing the muzzle upwards. It would just drop out. The problem is that when I try to close the bolt on the cartridge. It would not let me. I can move the bolt to about 10 degrees, the extractor would snap in place and then whole thing would get stucked. What I did was try all the other bolts I have from my other rifles of the same action and chamberings (this is what I meant by "different bolt sets") hoping one would work. They all did the same. They would close on empty chamber of that Tikka rifle but would get stucked in the same spot when I insert a cartridge in the chamber. I also tried with the extractor removed and didn't get any farther. I suspected a headspace problem and I began grinding the rim (they headspace on the rim) of my dummy ammo to see if it would help. From 0.064" I got it down to 0.040" before I was able to close the bolt on the dummy round. The dummy round's butt showed circular scratches that looks like from the bolt face as I turn to close the bolt. My dummy round, by the way, is a Graf 7.62x54r brass I full-sized with RCBS die and a 308 bullet on top.
So, now I'm of the opinion that if I removed 0.040" of metal from the bolt-face of the bolt-head I'm using with this rifle I just might be able to see find out if this Tikka rifle with like new bore could hit a paper plate at 25 yards. But I won't do anything yet until I hear different opinions and ideas. Thank you.

As a side note, I am not a gunsmith and my works on these rifles are limited to removing the action from the stock, cleaning the parts and putting them back together.
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Old April 4, 2007, 04:53 PM   #4
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Congratulations on your Mosin Nagant.

Before you start grinding try some other tests first.

Clean the chamber very, very well. Cosmolene from storage and lacquer from surplus comblock cartridges can build up in the chamber. With some old surplus rifles it may take a chamber brush wrapped in 0000 steel wool, dipped in solvent and driven by a drill motor.

Get a set of headspace gages GO and NO-GO and use them.

Disassemble the bolt head from the bolt assembly and drive out the extractor. Reassemble the bolt assembly without the extractor. Then try to chamber a cartridge. If it chambers, then examine the edges of the extractor for burrs. The extractor on a Mosin Nagant is fixed on the bolt head and has to turn through a 90 degree arc. Any burrs on the extractor will snag the edge of the cartridge rim. Also, if the rim is too large in diameter, the extractor will not be able to turn through the 90 degree arc. Do you have another brand of cartridge that you can try?

Finally, even though the rifle is surplus, the Finns did send many through a refurbishment facility and some were rebarrelled. If yours is one of those, it could be the barrel chamber was not properly finish reamed (this isn't very likely as the Finns were pretty meticulous in their rebuilds).
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Old April 4, 2007, 05:14 PM   #5
James K
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First, why is the case not seating? The 7.62x54R, like every other rimmed cartridge, headspaces on its rim, but it also has a shoulder. So the first thing I would do is take an empty case and cut it off 1/2" or so ahead of the rim. If that won't fit, then the problem is headspace at the rim.

I would not remove metal from the bolt. Instead, I would use the GO gage to make sure there is a rifle problem. If there is, I would use the proper chambering reamer to ream both the barrel end and also, if necessary, the chamber shoulder and neck.

Jim
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Old April 4, 2007, 06:33 PM   #6
straightpull
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Tikka 91/30

Thanks for the replies. I cleaned the chamber throughly making sure to remove all the things that shouldn't be there. I used bronze brass for .45 ACP wrapped with 0000 steel wool. Upon close inspection it looks like the rifle was short-chambered. When I dropped my dummy ammo and unfired empty shells from Polish and Hungarian surplus there is a noticeable gap between the rim and the base of the barrel. I compared it with other Mosins and it's obvious. I don't have GO and NO-GO gages. I might get soon. In the mean time, I would cut en empty case as suggested by Jim and see how it goes. I'll post the outcome. Thanks again guys.
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Old April 4, 2007, 09:31 PM   #7
James K
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Sounds like someone installed a new barrel and didn't finish the job, or there is something else in that chamber you didn't get out.

New barrels are always short chambered so they can be headspaced after installation. Even though the 7.62x54R headspaces on its rim, the chamber is still short and has to be finish reamed.

FWIW, if you need to ream, Brownells has the reamers, but you might not like the C-note cost.

Jim
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Old April 4, 2007, 10:09 PM   #8
t_baggins
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Try some different ammo. My mosin sniper wont hardly chamber czech silvertip. The Hungarian light ball surplus cycles perfectly though. Its very good ammo.
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Old April 4, 2007, 11:11 PM   #9
straightpull
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I tried Hungarian LB, Polish LB and Czech. Nothing worked. But as Jim suggested I cut some empty cases. The one that was cut to the point with shoulder intact, didn't work. The one about an inch from the rim worked perfectly. The last one I cut just to removed the shoulder and beveled the edge worked alright too. Having done this made me see the real problem. It looks like the solution (reamer) would be more than the cost of the rifle itself. But I have another idea that I need some input on (again). How about I get myself a die, just the body of a full-length sizer die then grind the bottom a little just so I can move the shoulder of the case back some, fire-form the case in the rifle and just neck-size afterwards. Any opinions? I already have the whole set-up for full-length and neck-size only for 7.62x54r and I've been transferring milsurp components to brass cases and non-corrosive primers so it won't be a big deal. All I need is the body of a FL sizer die. The reason I am leaning to this is because I am reluctant to touch the rifle itself and, of course, the cost. Thanks guys.
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Old April 5, 2007, 12:51 PM   #10
DnPRK
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There are a couple places on "teh intarweb" that rent chamber reamers.
www.reamerrentals.com has solid pilot finish reamer, 7.62x54r, for $26.
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Old April 5, 2007, 03:59 PM   #11
James K
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The custom ammo route sounds OK, but you just have to remember to keep it separate from your other ammo of the same caliber for your other rifle(s).

The reamer rental idea also sounds like something to follow up on and might be the best idea in the long run, but I would call around to local gunsmiths first and see if anyone has the reamer. It would probably cost less to have it done than to rent/buy the reamer.

Jim
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Old April 7, 2007, 08:45 AM   #12
Harry Bonar
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91-30

Sir:
Yes, I'm very familiar with the M.N. Those bolts aren't interchangeable - the ser # of the rifle is on the side of the bold body - especially so with a "rebuild."
The 91-30 is supposed to be the most accurate and many matches have been won with it.
The 7.62X74R is an excellent cartridge, approaching the 30-06!
7.62mm is .2999 in our English measure (actually British measure, metric was our invention) I think I'm right.
Harry B.
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Old April 7, 2007, 02:37 PM   #13
straightpull
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Thanks again for the input guys. I am learning each time.
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Old April 7, 2007, 03:49 PM   #14
James K
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The Russian Model 91 was called the "3 line" rifle, from the old Russian unit of measure, the "liniya", which was (I presume by coincidence) 1/10 of an inch or 2.54mm. That was bore diameter, just like our ".30 caliber" designation is based on the bore diameter. The Russian groove diameter was .308+ and their bullets normally run .3085 or .3090.

In metric designation, which I think the French invented, that comes out 7.62mm (or .300") bore, 7.82mm (.308") groove.

Jim
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Old April 8, 2007, 10:28 AM   #15
Harry Bonar
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91-30

Jim:
On all these rifles I've seen the action is fit so that the case is fit so that only the rim protrudes and the bolt closes on the face of the bbl with little clearance and the rim recess is in the face on the bolt - how in the world would they screw this up? Tight chamber specs. - that's unusual in a military deal!
Harry B.
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Old April 8, 2007, 07:09 PM   #16
James K
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Not really odd. Even though the headspace is on the rim, the proper distance from rim to shoulder had to be maintained. Spare barrels were still short chambered, so final reaming could be done with a normal reamer after installation. I suspect that a close examination would show that the rifle has a new barrel and someone just didn't finish the job.

After all, what did the arsenal crew care? The old junk was going out the door for real dollars and it was going to be someone else's problem.

Jim
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Old April 8, 2007, 10:12 PM   #17
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Many gunsmiths will rent a reamer to chamber a rifle. Cost is about $30-40 to rent one. Add the cost of the work to that. You are still looking at $100 to do the job.
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Old April 9, 2007, 05:11 PM   #18
Harry Bonar
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91-30

Jim:
Are headspace guages different in the Eropean countries from ours?
On the rifle you must be right but I cannot figure Tika rebuilds would be so sloppy.
I see what you mean - headspace was O.K. the case shoulder area needed reamed?
Harry B.
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Old April 9, 2007, 11:22 PM   #19
straightpull
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Tikka 91/30

My understanding is that Tikka scrapped some 14,000 or so 91/30 barrels dated 1944. Maybe mine was supposed to be scrapped too that's why they didn't bother finish up the chamber.

Last edited by straightpull; April 10, 2007 at 09:48 AM.
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Old April 10, 2007, 05:42 PM   #20
James K
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Hi, Harry,

A reamer (European or American) for a rimmed, shouldered round (.30-30, say), cuts the shoulder and throat as well as the rim seat. So if the barrel is new and not headspaced to the bolt, the chamber has to be short also to allow proper reaming for the headspace even though the headspace is only the rim space.

Jim
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