Wonder if any one could give some reliable tricks to reduce lock time on a Mauser 98. I know it is not necessary for a hunting rifle, just would like to see it a little quicker..

Thanks..

Spend $80 and buy a titanium firing pin and the strong spring that comes with it.

Mauserkid---

There are three ways to speed it up---

1) Shorten the distance the firing pin travels.

It's called speed locking. The back of the bolt is shortened by about .150" in a step extending from the cocking cam around the bolt only far enough to clear the cocking piece. Then a much stronger firing pin spring is installed.
The REAL trouble comes with retiming the sear with the cocking piece. It's easiest to switch to solid-rail cocking piece (FN/Mk-X) and cut it back by .150. (be sure to re-heattreat) The safety can be refitted at the same time with a notch ground in the cocking piece like a Swede.

2) Install a stronger spring.

This helps to an amazing degree on some old militaries with a relaxed spring in them. It's cheap.

3) Lighten the firing pin and cocking piece.

This works well but a stronger spring, as in number two above, MUST be installed. Otherwise there's not enough energy to ignite primers reliably.
The cocking piece and firing pin can be shortened on the back to lighten it by about 15%. You'll need at least a 30# spring to get reliable ignition, and then it's not a sure thing.

I do #2 on all custom rifles just because I want to KNOW that important part is new and strong. It WILL affect trigger pull (heavier) and it puts more force wear than normal on trigger parts, but I've never found it a problem.

The down side is that bolt lift becomes noticeably stiffer because the cocking piece cam is having to overcome a stiffer spring. Thats why the modified parts must be rehardened properly & glass smooth.

Re:
3) Lighten the firing pin and cocking piece.
This works well but a stronger spring, as in number two above, MUST be installed. Otherwise there's not enough energy to ignite primers reliably.

This statement contradicts a fundamental law of physics. The energy imparted to the firing pin comes from the spring – only. With all other things unchanged, if the weight of the firing pin assembly is decreased, its velocity will increase to the point where its impact energy remains unchanged. Conversely, if the weight is increased, velocity will drop to the point where the impact energy is again unchanged.

If an ignition problem occurs with a lightened firing pin/striker assembly, it must be due to something other than just the change of weight.

Redrover, what you said is true but your forgeting that the force on the fireing pin is of no importance. It is the energy that is transfered to the primer that is important. And this energy comes from the force of the spring and the moment of the firing pin. Sence the moment of the fireing pin is reduce as you liten it you need to compinsate by increaseing the spring force. The heavier spring brings every thing back into equilibrum with a shorted time span of movement.
Ray

redrover---

Great question. I'm don't know......but I think it has to do with the difference between energy and momentum?

I somewhere a long time ago read why the commercial M-98 Magnum Mausers, and some others, have an extended (heavier) cocking peice, "for more positive ignition under tropical conditions.....". It sounds like a commercial and probably was.

Assuming the spring in these guns are the same, it means there's more weight and less speed and the energy would be the same?

I have the formula for lock time I can scan for you if it'll help solve the mystery.

Me an algebra have had a long, but unsatisfactory, relationship.

I have always wondered about the necessity for the stiffer spring with a lighter pin myself. I have lightened strikers without changing the springs with no apparent ill effects.
Stuart Otteson in his book on bolt actions claimed it was striker energy in combination with adequate penetration of the primer by the pin that was required for reliable ignition. If I recall correctly, he contended that striker velocity was as important as striker weight.
One explanation I heard for the increase in spring rate was to offer more support to the primer cup to prevent blanking. This was said to be necessary due to the reduced inertia of the pin. Perhaps some testing is in order. I have a titanium pin for a mauser. Ill try it with and without the heavier soring and see what effect
Regards, Bill.

I put a lightened steel striker in my Glock, hollow and fluted to half the weight of the factory part.

It is a new G26, in the 350ish rounds before with the factory striker no problems. In 200 rounds fired with lighted striker, 1 falure to fire. Guessed to be from a light strike. There was a half depth impression on the primer. Second time thru the pistol, it fired.

Replaced the Factory striker. 300plus rounds since, not a second malfunction. Only falure to firer was with a lightened striker and a stock weight spring. Ammo in all instances, S&B 115gr FMJ.

With a lightend striker(firering pin) and a stock weight spring, you may never have a faliure to fire. It is a judgment to which is most needed. Tight little groups or the gun firring. My G26 is a carry gun, the factory striker will stay in it from now on.

Kristofer

[ 11-26-2002, 11:18: Message edited by: KBGuns ]

The main principle which comes into effect in this issue is the Law of Conservation of Energy, which simply states that energy cannot be either created or destroyed. i.e. it can only be transferred/transformed from one state to another. When we cock a rifle, some energy from our arms is transferred to the firing pin spring and stored there, and this is the amount of energy which is released upon firing – no more, no less. Actually, a little bit of it will be lost because of friction, but in a properly designed and maintained firing system, it won’t be very much.

The impact energy of the firing pin assembly is half the mass multiplied by the impact velocity squared. (or the velocity raised to the second power, to put it in more precise mathematical language) For a given spring configuration and firing pin fall, the acceleration of the pin, and hence the impact velocity of it, will be determined by its mass, so a ‘boxed in’ situation exists. Increase the mass and velocity automatically decreases, and vice-versa, but the impact energy remains constant.

However, impact momentum (or impulse) which is simply mass multiplied by impact velocity does NOT remain constant. At a given impact energy level, a heavy, slow moving firing pin will have greater momentum than a lighter, faster one.

A detailed analysis of this subject, and lock time, which is inextricably tied in with it, can be found in the book ‘The Bolt Action’ by Stuart Otteson, with further material and formulae in the book ‘Benchrest Actions and Triggers’ by the same author.

It might appear intuitively obvious that for a set energy level, a high momentum firing pin impact would be the most effective at setting off a primer. However, Otteson states that research by Winchester (described in U S Patent 3,056,226) and studies by both SAAMI and the U S Army show that the exact opposite is true. Apparently they all found that when firing pin impact energy was getting down near the lowest acceptable levels, a light, fast moving firing pin – low momentum type - was actually the more effective. It stands to reason when you think it through – the faster the pin is moving at impact, the more rapidly it transfers its energy to the primer, and this would presumably aid ignition.

There are probably many reasons why older military rifles such as the Mauser 98, the Springfield and the Enfield have heavy, long-fall firing pin systems with relatively soft mainsprings. The mercury and the potassium chlorate based primers of those days may well have needed a heavier whack than modern types require. Being battle rifles, the designers doubtless wanted to build in a substantial amount of surplus firing pin energy, in the hope that the rifles would still fire after being dragged through water, mud, sand, etc. and given minimum maintenance. These three rifles as issued all have firing pin impact energies in the range of 130 to 150 inch-ounces, whereas most modern bolt action sporters are in the range of 70 to 90 in-oz. This is considered adequate for modern primers. Firing systems with high impact velocities and fast lock times almost inevitably require powerful, high-suppression main springs, and these are certainly no aid to stripping down a bolt under battlefield conditions. Besides, a soldier in a ‘kill or be killed’ situation doesn’t care if his rifle has a lock time of 2 milliseconds (very quick) or 6 milliseconds. (fairly slow) He just wants to be sure that it will fire when he pulls the trigger!

So where does all this leave somebody who wants to speed up the lock time of a Mauser 98? I don’t know for sure, because the only speed locks I have any first-hand experience with have been Enfield jobs. The Sarco and Numrich kits which gave a firing pin fall of something under 1/4in proved to be less than satisfactory. A Dayton-Traister kit which gave a fall of 0.30in worked quite well. All these kits include replacement main springs which are much more powerful than the original. Reducing the weight of the D-T firing pin and striker slightly by a some discrete milling and grinding should have theoretically reduced the lock time a further fraction of a millisecond, without affecting the impact energy, but in fact it made no perceptible difference.

I once tried using an extra powerful spring in an M17 Enfield, with no other changes, but it wasn’t exactly an unqualified success. It did improve the lock time, I'm sure, but because it was a cock-on-closing action, reloading was awkward at the best, it thumped the striker down with the force of the out-house door slamming in a southerly gale, and the trigger pull became noticeably heavier. I worked out the impact energy using Otteson’s formulae, and it was something terrific – not far short of 200in-oz, as I remember. I soon put the original spring back in.

Like the Enfield, a military M98 with an ‘up to spec.’ mainspring has considerable surplus firing pin energy, so in theory, it should be possible to shorten the fall and speed up the lock time somewhat without reducing that energy to the marginal level. Whether or not it would be worth all the cutting, grinding, re-hardening, polishing, etc, that would be necessary to do the job properly is a moot point, though. It would be costly, and probably only reduce lock time from a bit over 5 milliseconds to maybe 3.5 milliseconds. Not a huge gain.

Think of it like this: A heavy hammer (the firing pin & cocking piece) requires LESS momentum to do the same work than a lighter hammer / firing pin & cocking piece does. The reverse is also true. A lighter hammer takes MORE momentum to do the same work that a heavy hammer does. Its the weight of the MASS hitting the primer at a sufficient momentum to ensure consistant detonation.

[ 11-26-2002, 18:17: Message edited by: Bear Claw ]

I think Bill Leeper got it.

One of my all time best practical jokes on a fellow shooter was to change his firing pin spring (M-98) between his load development test. A lighter spring would show a puckered primer at MUCH less pressure. He would reduce the load and I'd increase the spring.....he'd raise the load and I'd change back to a light spring and the primer would pucker or leak. It about drove him nuts.

I *think* the increased spring overcomes the reduced inertia of the firing pin assembly and keeps the primer in one piece.

Great post redrover! When I read Otteson's formulas my eyes cross and I realize what I don't know.

So after reading all this I tried to put it into terms I understand and here's my take: Would your rather be hit by an ounce of photons (very light) at over 183,000 miles per second, or one ounce of lead at 600 feet per second?

You must state whether the photons are compacted as in a photon torpedo.lol

Not to be a stickler but, an ounce of photons is still an ounce, no matter how light the individual photons are.

An ounce of photons moving at "c" would probably obliterate a large portion of our planet.If they where in a solid form, say as dense as a lead bullet.

How's that for transfering energy to the target?

Do the math, the energy would be enormous!

[ 11-26-2002, 20:19: Message edited by: TERRY8mm ]

Redrover,
Consider also the military primers are a bit harder than commercial primers.

Re: When I read Otteson's formulas my eyes cross and I realize what I don't know.

Aw, come on – they are not THAT bad! :-) At least those formulae presented in ‘Benchrest Actions and Triggers’ aren’t, and if you have even a fairly basic scientific type calculator handy, they can be solved quite readily. One thing you DO have to watch, though, is that when using the formula for calculating lock time, which involves a cos-1 factor, the calculator must be set to working in radians, NOT degrees. The first time I tried using that formula I got a crazy answer, so then I tried working through the example given – and when I realised that my answer was about 57 times greater than the correct one, the penny finally dropped.

Going back briefly to the subject of reports of guns and rifles working OK with standard firing pins but misfiring when fitted with lighter ones. Theory says it can’t happen, and the laws of physics aren’t subject to random change, so what MIGHT be a plausible explanation for it?

How about if there was more friction present in the firing system than there should be? Say, caused by rough or burred parts, a slightly bent firing pin, mis-aligned guides, a buckled main spring, or something like that. Could a light, fast moving firing pin be more adversely affected by this than a heavier, slower moving one, enough to make the difference between the gun firing or not? It doesn’t sound like a totally convincing explanation, and it would probably be difficult to prove or dis-prove without some elaborate engineering laboratory equipment, but offhand, I can’t think of a better one.

Anyone got some better ideas?

When I was a small boy I was told all about momentum and energy in gun designing.
Now I am 51 and feel pretty smart.
Then I read Redrover's first post to this thread, "The energy imparted to the firing pin comes from the spring �"

I realize now I was asleep at the switch while reading...