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Straight Bolt Vs. Bent....Why?

35K views 33 replies 28 participants last post by  Leon 
#1 ·
I was recently showing a friend some of my rifles and he came up with a question that had never ocurred to me, as simple as it is. Why do so many early bolt action rifles have a straight bolt handle, and not a bent one?

I can imagine that one answer would be for cost and time of production issues, but is there any other reason? Also, it seems that American and British weapons had bent bolts fairly early on. Why did the Mausers, Arisakas and Mosins retain the straight handle for so long? The advantages of a bent bolt are obvious. At least, to me. Is there another reason/advantage to retaining a straight bolt handle?

Thanks,

John
 
#3 ·
My guess:

The clunkier the action the more likely the straight bolt for better leverage. Bu then there were Mausers with stragiht bolts.

The belt bolt is better at avoiding snags.

I suspect that tradition, national pride, manufacturing capabilities, urgent combat needs, and any of a dozen other inputs decided these things in some places.
 
#6 ·
That was the first thing my buddy thought of, too. Very possible.

Danus ex,

That's some good insight. My first thought would be a faster handling action, due to the shorter distance required on the bent bolt. As for scope use; of course it's needed, but I don't think that was the original reason for using a bent bolt, as most of the early rifles that had them were not using scopes, at least until much later in their design "career". The snagging issue also has some merit.

Good stuff, guys. I would love to hear other ideas or, better yet, any documentation.

Thanks,

John
 
#5 ·
It's the amalgam called "customer demand". To me, the bent bolt only has three real advantages: the ability to mount a scope directly over the action (major, depending on your requirements), shorter distance between the trigger and the bolt handle (minor), and a somewhat reduced likelihood of snagging things (minor).

Straight bolt handles likely made more sense to more militaries. Unless a bent bolt rifle's stock has a nice deep inlet, straight bolt handles are easier to grab, especially when wearing gloves or mittens. It's somewhat easier for a left handed shooter to work a straight bolt action. Leverage is part of it, too: the straight bolt encourages right-handed shooters to grip the handle while their whole hand, coming up from underneath and putting the knob at the end of the handle in their palm instead of in their fingers/fingertips, like most people do with a bent bolt.

Personally, I don't use optics and I regularly shoot in the winter. Give me a straight bolt 10 times out of 10.
 
#7 ·
The Mosin straight bolt, in cold weather or sticky empty casing conditions, provides much better leverage to cycle the bolt. When you get a stuck empty in a bent bolt, it is difficult to apply the necessary force to bang it open whereas the straight bold handle can easily be banged hard against any surface to get the action open. A bent bolt handle is required for any type of scope in order to clear the scope. Compare a balky Mauser against a Mosin when the empties are sticking in the chamber and you can rapidly appreciate the difference in leverage!
 
#9 ·
I came upon this a while back while searching for the same answer. I can't vouch for it's veracity, but it made sense.

Supposedly, up through the World War I era most European militaries were still couched in the "Napoleonic" mentality of warfare. This meant armies attacking in massed frontal assaults on enemy positions. Rifles were designed, like hand grenades, to be "offensive" or "defensive". A straight bolt rifle allowed the infantryman to cycle and fire from the hip without having to stop his advance, thus they were of the "offensive" type. The straight bolt made this easier and faster than a bent bolt. The bent bolt, however, was designed to be easier to fire from "defensive" positions, firing from the shoulder or prone without having to remove the rifle from it's aimed position. To my knowledge, England and the US never had a straight bolt rifle because they trained their riflemen from a different philosophy of warfare, putting more emphasis on aimed shots rather than mass fire.
 
#14 ·
I came upon this a while back while searching for the same answer. I can't vouch for it's veracity, but it made sense.

Supposedly, up through the World War I era most European militaries were still couched in the "Napoleonic" mentality of warfare. This meant armies attacking in massed frontal assaults on enemy positions. Rifles were designed, like hand grenades, to be "offensive" or "defensive". A straight bolt rifle allowed the infantryman to cycle and fire from the hip without having to stop his advance, thus they were of the "offensive" type. The straight bolt made this easier and faster than a bent bolt. The bent bolt, however, was designed to be easier to fire from "defensive" positions, firing from the shoulder or prone without having to remove the rifle from it's aimed position. To my knowledge, England and the US never had a straight bolt rifle because they trained their riflemen from a different philosophy of warfare, putting more emphasis on aimed shots rather than mass fire.
The British Lee Metford rifle used in the Boer War has a very slight downward bend. It was only after the Boer War did the British get really serious about rifle marksmanship, and then the SMLE No 1 Mk III got the bent bolt handle.

The Russians were freed from "Napoleonic" tactics during the three Battles of Plevna during the 1870's Balkan campaign. There the Russians improvised fire and maneuver tactics. The Berdan II, the most modern Russian rifle in that campaign, has a slightly upturned bolt handle. The Mosin action bears some similarity to the Berdan II, so conceivably the bolt handle was made straight in the interests of familiarity, as well as economics.
 
#11 ·
only two reasons I can think of for a bent bolt are optics and speed. When bolt action rifles were first introduced, optics weren't much of an option, so a bent bolt wasn't needed.
When cartridge rifles were invented, and followed not too long afterward with magazines instead of single shot, some governments were afraid that their armies would break the bank by shooting too much ammunition. They were accustomed to buying ammunition for an army that shot single shot muzzle loaders and went into shock at the cost of the ammunition that a "modern" rifle could consume. Since moving the bolt handle as close to the shooting hand as possible can speed up the rate of fire (and consumption), they may not have seen any advantage to it. Ease (and lower cost) of construction would be another factor.
Many early rifles with magazines had magazine cutoffs also, largely to keep a rifleman from burning through too much ammunition.

y'all have a good day, Keith
 
#12 ·
Most pre-1900 carbines had bent bolts, why? To reduce the chances of the gun catching on something while slung, and to reduce the damage to the rider getting hit with the bolt knob. Many short rifles had bent bolts too, since gunners were more likely to be working or riding with the gun slung. Most rifle bolts were straight, because it was expected that the gun would be in the soldier's hands and the straight bolt added leverage and was cheaper to produce. Thus, originally the bent bolt was originally a compromise for guns which were usually slung.
 
#13 ·
Try getting whacked by the end of a straight bolt on a slung rifle and you'll know why there was a general switch to the same sort of bent bolt the cavalry had to use.
 
#17 ·
The only explanation that I agree to.
Optics were a much later afterthought & were used on a limited basis.
Didn't the Krag use a bent bolt?
 
#19 ·
Bent bolt handle in 1869:

 
#20 ·
another method for quickly operating a rifle with a straight bolt handle: while pushing upward (counter clockwise) on the straight bolt handle with the palm of the shooters right hand, the shooters left hand rotates the rifle in a clockwise motion. lots of leverage to remove a stuck case and quickly reload. best, john
 
#21 · (Edited)
on the other hand...maybe its about how the bolt cocks the action. If it cocks on opening of the bolt, mausers, springfields etc then you really have to use the operating hand PALM UPWARDS to get enough leverage to open the action, break free the 'primary extraction' of the fired case and cock the firing pin. This means that at some stage you have to 'turn the hand around' to close the bolt...that of course is much easier with a 'straight' bolt handle...

The Lee Enfield of course cocks on closing...much easier to open with the trigger finger and thumb of your firing hand...then with the momentum of the full arm and elbow you ram the bolt home cocking the action and chambering the cartridge. No turning around of the operating hand is needed.

The proof of the pudding??? rapid fire of the Lee Enfield that cant be matched by Mauser type cock on opening actions.
Then again...for shooters that have been brought up on cock on opening actions....they probably dont know any difference. And of course to be fair I should also point out that SOME Mauser actions do cock on closing....the P14/M17 (both have turned down bolt handles) and the M96 Swede (straight out bolt) being examples....the Arisaka of course has a bit of an each way bet...some cocking is done on the opening of the bolt and the final bit on the closing...
 
#24 · (Edited)
It's very likely a combination of most of these answers, to my mind. I especially like metfordman's take on it, as I enjoy shooting my Enfield's cock-on-closing action. ;)

Also high on my priority list is the issue of fast and cheap(er) production. I believe that this was paramount in Russia's devlopment of our subject rifles. They had a lot of soldiers, so they needed to arm them with something that was cheap and reliable. Straight bolts filled those requirements nicely.

This has already been mentioned several times, but leverage is a major consideration. A rifle that is fired multiple times every day and dragged through mud with minimal (if any) cleaning needs some "oomph" to cycle properly. Case in point, I had a '42 Izhevsk with matched receiver and bolt. The headspace was just a little tight, and with certain types of surplus ammo, required a bit of a slap to close. With a bent bolt, a man of average strength would never have been able to operate this rifle effectively. However, with the extra leverage provided by the straight bolt, even the most downtrodden conscript soldier could have used this weapon.

I just don't think the ability to scope a rifle was much of a consideration, at least up through the midpoint of the 20th century. The average service rifle was built with the average grunt in mind, and the average grunt just doesn't need a scope on his rifle.

There are many other good reasons that have already been listed on this thread, but these are my favorite.

PSY
 
#25 ·
supprised noone else mentioned this,at the end of the reloading foward stroke with the heel of the hand on the ball of the bolt handle ,your trigger finger is neatly aligned with the trigger.
Saw a doco on rapid fire from a SMLE which demonstrated this.is all about speed,i also heard/read the same thing for the MAS series if bolt rifles
 
#26 ·
regarding the straight bolt vs bent bolt; it is easier to close a straight bolt, as the "moment of Force" is further out on the straight bolt ( ie, one has a longer lever...Archimedes lever and fulcrum principles, so it is easier to open and Close a straight bolt in "Sticky" situations; This is countered by the lee-Enfiled's "rapidity of fire" when used with "clean" ammo, and the fact that the 303 case has a thick whacking great rim to catch an equally robust extractor claw, for Primary and secondary extraction. ( same for the Mosin, although the extractor is not as Robust, and the Lever is straight, but shorter.)

All the other advantages, ( winter use, etc) are valid pro's for the straight Bolt...Only the cavalry back-slung carbines really needed the bent bolt, to avoid digging in and snagging.

Scopes have really no entry at all, because they are a civilian invention, firstly, and the Bolt handle even if bent, has to be adaped one way or another in either a civilian or Military rifle, or "High" or "Offset" Mounts used, because of the nature of the bolt handle ( ie, MN91/30, offset scope and Long Bolt handle.) Gew 98 SSG, High offset mounts, wedged down bolt handle, very little clearance between open handle and scope eyepiece.

So, there we are...the straight handle is better mechanically, and the bent handle may be faster ( depending on the rifle design...rear lockers and cock on closing). So, Horses for courses!!!

Doc AV
( I shoot both types, but prefer straight bolts to bent; except for the MAS36 and the SMLE.)
 
#28 ·
regarding the straight bolt vs bent bolt; it is easier to close a straight bolt, as the "moment of Force" is further out on the straight bolt ( ie, one has a longer lever...Archimedes lever and fulcrum principles, so it is easier to open and Close a straight bolt in "Sticky" situations; This is countered by the lee-Enfiled's "rapidity of fire" when used with "clean" ammo, and the fact that the 303 case has a thick whacking great rim to catch an equally robust extractor claw, for Primary and secondary extraction. ( same for the Mosin, although the extractor is not as Robust, and the Lever is straight, but shorter.)
...
The MN bolt handle is short; half as long as the straight Mauser bolt handle, so leverage is not so powerful.

The factor was cost. Russia in the late 19th Century always had cash shortages. There was no such thing as deficit spending in those days, and the Imperial Russian ruble was one of the strongest European currencies until WWI. The paper money was backed by both gold and platinum.

It would have made better sense for the bolt handle to be at least 50% longer in order to provide the optimum leverage. The stubby bolt handle was probably a compromise in the name of production economy and ergonomics, i.e. not projecting out so far as a Mauser or Mannlicher bolt handle, but being "good enough" both for leverage and avoiding snagging.

The other factor to consider is that the M91's expected targets were the Austrians. Interestingly, the Austro-Hungarian army responded to the Russian's adoption of the MN with their repeater carbine M90 and later the M95 rifle, both with straight-pull actions.
 
#30 ·
What a great thread! There are many very plausible explanations presented in the above posts. May I humbly suggest that forging a bolt with a straight handle requires much simpler and cheaper forging dies than would be required to forge a bent bolt? At the very least, the red hot cherry would require an additional production step to put the bend in the handle.
 
#31 ·
not every sniping rifle had have a bent bolt

but it was a big plus

the cold winter theory is maybe rigth for the russian. they never change for the bent bolt for the carbine's.

this is the last model M 44 - straight bolt - and the bent bolt for sniper rifles was always in production.
 
#33 ·
Interesting question I have often wondered about. I've never heard a definitive reason but many here sound solid. I can say the bolt on my .303 Enfiled is bent and is very smooth and fast. My mausers have straight bolts and are very smooth also. Mosin's not so smooth by comparison. One drawback on the straight bolts is spacing. You need a lot more space in your gun cabinet or safe with the straight bolts. I have to custom build mine to account for the wider spacing.
 
#34 ·
Interesting question I have often wondered about. I've never heard a definitive reason but many here sound solid. I can say the bolt on my .303 Enfiled is bent and is very smooth and fast. My mausers have straight bolts and are very smooth also. Mosin's not so smooth by comparison.
My Finn's are smooth and operate easily. The MN bolt is a bit loose in its track, so bearing down on the bolt handle can make it bind a bit. I find with a light touch the bolt operates freely and smoothly. Proper lubrication makes a difference too.

Of course, nothing in my collection can equal my Krag for a slick working bolt. I have two Finn's with New England Westinghouse receivers, and they have a different feel than the rifles with Tula, Sestroryetsk and Chattelerault receivers. The NEW rifles are not hard or rough in operation, they just feel different.


One drawback on the straight bolts is spacing. You need a lot more space in your gun cabinet or safe with the straight bolts. I have to custom build mine to account for the wider spacing.
The only straight-handle rifle in my rack is a Swedish M96, with "SA" mark of course. Since the Swede's cock on closing, I just open the bolt.
 
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