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Old January 20, 2019, 01:25 AM   #26
briandg
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The cocking knob on the end of the firing pin won't do squat to deflect gasses from a ruptured case. That was a function of the original bolt shroud, where the original wing safety was located. Same as the 98 Mauser, which does not have a cocking knob on the firing pin.


As far as I know the only reason for the bolt knob was to either cock or decock the weapon. Lowering the pin and carrying the weapon with the pin down wasn't exactly the plan, i don't think, but our military had spent a lot of time fighting in cold weather, and with injured hands. You had a big knob to grab. (oh, come on, leave that be. there's no other way to describe it.) Several others such as the krag, arisaka, and enfield had enhanced grabbing bolt heads. Mauser didn't seem to see a point in it. No current models seem to carry a cocking knob, the current designs all depend on manual safeties that don't allow the pin to get near the primer.
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Old January 20, 2019, 01:24 PM   #27
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As far as I know the only reason for the bolt knob was to either cock or decock the weapon.
You're right, that's pretty much all you can do with it.

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Several others such as the krag, arisaka, and enfield had enhanced grabbing bolt heads.
I know what you are talking about, but some others might not, so a small point of clarification about the usual use of terms is in order.
"Bolt knob" is usually used referring to the knob on the end of the bolt handle, and "bolt head" is commonly used referring to the front of the bolt, where many (but not all) designs put the locking lugs.

What we are talking about is the rear end of the firing pin assembly, which is usually called the "cocking piece".

The design of the cocking piece on the different military bolt guns shows either the intent of the designers, or the requirements of the purchasers. One thing to keep in mind is that the designs all pre-date 1900 or are based largely on designs that pre-date 1900. An era when misfires, hangfires and ruptured cases/primers were much, much more common than today.

I believe the intent of an easily grabbed cocking piece knob was so that the event of a misfire (dud) weapon could be recocked without operating the bolt. A "second strike" capability. And, it could also be used to decock the EMPTY rifle without dry firing it.

I don't think any military would have had troops lowering the firing pin (decocking) with a live round in the chamber. In all the designs I'm aware of, that would put the firing pin in contact with the primer, which is not even remotely a safe way to carry the rifle, as any blow to the back of the firing pin would go straight to the primer, firing the round.

The British Enfield (SMLE) has an "enhanced grabbing" cocking piece, its large, flat, and grooved for that reason, and is a carryover from the original Enfield design, which dates from 1888.

The large knob at the rear of the Arisaka bolt is the safety. It is operated by pushing in and turning it, to put the safety "on". Pulling on that knob will not cock the rifle.

The Moisin Nagant has a large knob at the back, which is also the safety, but can be used to cock or decock the rifle.

The Mauser 98 doesn't have a cocking piece knob, though there are a pair of slots in the cocking piece where a makeshift tool could be "hooked" to pull the cocking piece back, without working the bolt.

The Krag has a cocking piece knob, allowing for an easy "second strike" on a primer. The 1903 Springfield has that same knob, and I believe that it was carried over from the Krag to the Springfield at the request of the Army. (just my theory, I have no proof).

I think it is a reasonable theory, because of the second feature shared by the Krag and the Springfield, the magazine cut-off. I think both these features, found on the Krag were carried over to the Springfield because the Army wanted them (at the time). Note that later (newer) designs don't have either of them. The US 1917 Enfield comes to mind. Neither a cocking piece knob or a magazine cutoff on that design. I think that after the 1903 design, it was finally recognized that neither feature was really needed, and was simply extra manufacturing expense for something that wasn't very useful.

As far as I know, the US was the only nation to use the magazine cutoff, and we dropped it after the 1903 Springfield design. The idea sounds useful, allowing the solider to single load rounds for aimed fire, while keeping the loaded magazine in reserve, available at the flip of a switch for "emergencies" but in practice turned out to be of little or no practical value.

Here's a little known tidbit, showing how some ideas carry on, even when they have already been largely discarded. The "second strike" capability (recocking the gun for a second strike on the primer, without working the action) can also be done with the M1 Garand and the M14 rifle! Even the M16 can be "recocked" without moving the bolt, though doing it is more awkward than doing it with the other rifles named.

The 1903 Springfield is a hybrid of Krag and Mauser features, enough Mauser that a court eventually ruled that we had to pay Mauser royalties on our use of their design. And, we did, though Mauser never got a penny of them, we did pay...
(the payments were held in escrow due to WW I, and after the war, seized as part of Germany's "reparation payments". Neither the German government nor Mauser ever got any of the money.)
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Old January 20, 2019, 02:03 PM   #28
Jim Watson
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As far as I know, the US was the only nation to use the magazine cutoff,
Lee Metford and Lee Enfield up through No 1 Mk III had magazine cutoffs. Dropped on the No 1 Mk III* for wartime production.

The Ross Mk II rifle had a magazine cutoff.

The difference being that the Empire carried on with the bolt action for a long time and kept updating it while we moved on to automatics.
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Old January 20, 2019, 07:02 PM   #29
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briandg:

I am kind of straining my brain around this, prior to WWII what cold weather battles did the US fight? US got to WWI summer of 1918. 1903 designed before that. All fights were tropical I can think of prior.

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but our military had spent a lot of time fighting in cold weather, and with injured hands. You had a big knob to grab.
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Old January 20, 2019, 08:12 PM   #30
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It seems to me that someone intended this as a target rifle.
This is an old school O3A3 target rifle.

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Old January 20, 2019, 08:25 PM   #31
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Originally Posted by 44 AMP
The "second strike" capability (recocking the gun for a second strike on the primer, without working the action) can also be done with the M1 Garand and the M14 rifle!
44 are you refering to just pulling the bolt back a little on my Garand, but not enough to eject the cartridge, which does recock it for a second strike?

And thanks for the little primer on WW1 and 2 military bolt guns!
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Old January 20, 2019, 08:28 PM   #32
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This is an old school O3A3 target rifle.
Hawg that is a BEAUTIFUL rifle... gorgeous. How does it shoot? Had the trigger been lightened at all?
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Old January 20, 2019, 10:02 PM   #33
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44 are you refering to just pulling the bolt back a little on my Garand, but not enough to eject the cartridge, which does recock it for a second strike?
No, I am not referring to that at all. There is another way, and does not involve moving the bolt at all.

I am very tempted to leave it at that, and see how many can guess, but since you asked, you do it with the trigger guard!

Unlatch the trigger guard at the rear and rotate it forward like a lever gun, the same as you do to take the gun apart. This will cock the hammer. Close the guard back up and latch it and you are ready to try that "second strike" on the primer without ever needed to work the bolt at all.

This will work on the M1 Garand, the M14 and the M1A. (with the standard GI trigger group) Not sure why one would want this ability, but it is there.

With the M16 (and all other AR variants) push out the rear takedown pin, hinge the rifle open and recock the hammer by hand, then close and push the pin back in.

Most of us would simply cycle the action and eject the unfired round loading a new round, but if for some reason you do want to recock these guns without opening the bolt at all, it can be done.


Now, want to bet me I can't lower the hammer of a 1911A1 using only the hand holding the gun?
one fellow actually did....

Once....
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Old January 20, 2019, 10:23 PM   #34
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Hawg that is a BEAUTIFUL rifle... gorgeous. How does it shoot? Had the trigger been lightened at all?
Thanks! It is a full fledged target rifle. The trigger is set at 3 ounces. From a bench it makes a single bullet sized hole at 100 yards. At 250 yards it makes a small cloverleaf. At 500 yards you can cover the groups with a quarter.
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Old January 21, 2019, 12:18 AM   #35
M88
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Originally Posted by 44 AMP
Unlatch the trigger guard at the rear and rotate it forward like a lever gun, the same as you do to take the gun apart. This will cock the hammer. Close the guard back up and latch it and you are ready to try that "second strike" on the primer without ever needed to work the bolt at all.
Well I'll be damned... just tried that, and it works! Well... of course it does if I learned it on here from guys like yourself. Another little tidbit about my Garand's I never new. Now THAT makes me like my older trigger guard style like the one in the above pic here, over the newer one below, because it's easier to do that little trick.

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File Type: jpg 000 garand1.jpg (66.5 KB, 87 views)
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Old January 21, 2019, 12:34 AM   #36
M88
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...At 500 yards you can cover the groups with a quarter.
Now THAT is impressive... I wish I had a place around here where I could safely SHOOT 500 yards without houses roads or other properties jeopardized if I did. I can manage 100 yrd shots safely on my property, but that's all. Best I can do after that is a range 2 hours from here that has a 300 yarder. Again, beautiful rifle, love the early wood/ late wood pattern. (tree rings when cut flatsawn rather than quartersawn).
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Old January 21, 2019, 08:42 AM   #37
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It is impressive. When I first got it I sighted it in at 100 yards and once it was zeroed I couldn't see any new holes. I even went and looked at the backboard thinking I was missing the whole target. When I finally figured out they were all going thru the same hole I was like WOW!!! It was built by a master builder who is sadly no longer with us. The barrel was made by a man that built sniper rifles for the military during Vietnam. I think his name was Mike Stone but I could be mistaken. After he got out he started making his own barrels but didn't stay in business long. This one was a NOS he'd had waiting for a special project but let me have it instead.
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Old January 21, 2019, 10:58 AM   #38
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Originally Posted by M88 View Post
Again, beautiful rifle, love the early wood/ late wood pattern. (tree rings when cut flatsawn rather than quartersawn).
It looks like a laminated stock. For a solid stock, I believe quartersawn cut is preferred for its stability. The ray fleck pattern is a side benefit, if you like the sort of things as I do. Laminated stock can be cut flatsawn because of the superb stability of the wood.

It is mostly wood shop talk. I'm just an amateur who happens to have dealt with a few gun stocks with warped barrel channels.

-TL

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Old January 21, 2019, 12:02 PM   #39
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Bushnell 1.75-5x32 designed for shotguns and muzzle loader's? Amazing! Where did you come up with that?
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Old January 21, 2019, 01:08 PM   #40
M88
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Originally Posted by Don Fischer
Bushnell 1.75-5x32 designed for shotguns and muzzle loader's? Amazing! Where did you come up with that?
I knew little about the Bushnell Trophy, so looked it up, here is what I found on opticsplanet... about half way down the page they talk about this scope as short range etc. That's where I got my info. If you know something different, let us know. Again, knew nothing about the scope, had to go digging.

https://www.opticsplanet.com/bushnel...pe-731500.html
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Old January 21, 2019, 01:23 PM   #41
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It looks like a laminated stock. For a solid stock, I believe quartersawn cut is preferred for its stability.
I stand corrected. Thought it was slow growth pine sliced flatsawn, which would show off that dark latewood. I happen to be a woodworker myself, and know all to well that wood moves with the weather (hygroscopicity). My Shaker table tops for example are always quartersawn for stability. I've built a full blown shop over the past 30 years, slowly upgrading from weekend handyman grade to more professional stuff that should last my lifetime other than replacing a motor or bearing here or there. With the acquisition of a metal lathe and a Mill/Drill machine a while back IF I ONLY KNEW HOW TO FULLY USE THEM, I thought I may even be able to do a little gunsmithing. Alas, there just isn't enough time in life for ALL the fun stuff we want to do in retirement! Thanks for pointing that out, the stock.
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Old January 21, 2019, 04:33 PM   #42
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It looks like a laminated stock.
It is laminated. Here it is next to a Fajen 03A3 sporter stock.

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