Reduce Locktime on a Ruger SRH?

[Cthulhu]

A coworker expressed interest in getting a Ruger .454 Super Redhawk for his big bore DA revolver needs, mainly hunting deer and informal target use. His big concerns involves locktime and inertia of the hammer during single action fire. While that should mean little when shooting from a rest at stationary targets, he is worried about the detriment to accuracy on live targets shooting off hand.
Taking a cue from the 1911 hammers, he wants to skeletonize the hammer of the SRH to reduce mass. While it should work in theory, I was curious if anyone else has done this, or at least looked hard at it. If so, what were the results? Anyone have details on the specs, material properties, and heat treating of Ruger SRH hammers?

 

[Jim March]

Wrong answer.

OK, first, the way to speed the hammer travel with no "downside" is to take everything completely apart and fine-polish the sides of the hammer and trigger, and the interior frame surfaces they rub against. Ditto the hole in the hammer that it pivots on, and the pivot pin. Basically get rid of most of the friction in these areas, WITHOUT taking lots of metal away (read: VERY fine-grit (600) sandpaper or a felt Dremel polishing wheel with a real light abrasive like toothpaste). Also: don't screw with the "sear engagement surfaces" where the hammer contacts the trigger (that's an "expert only" area).

This hand-mirror-polish job will take hours but will reduce friction, allowing the hammer to fall faster. It will also slick up the action even with factory springs. Another point: if this is a used gun, esp. 5+ years old, swap all the springs while you're in there.

That will give you less lock time while not hurting a single thing...other than your time invested, this is a "zero downside" modification, unlike most things where there's a tradeoff of some sort.

The next step up: measure the hole where the hammer pin goes. Find a ball bearing set with the same interior hole and the same or a little less width than the hammer...drill out the hammer to take the bearing unit. It's got to be a HIGH END roller-bearing set. This seriously reduces hammer friction, some gunsmiths have done this for very high end pieces.

Reduce the hammer weight too much, you risk unreliable ignition.

--------------

Another thing: take any DA revolver that can also be cocked SA, and UNLOAD it. Now hold it up sideways and cock it...look at where the hammer is resting. Lower the hammer back to normal, and now stroke it through a DA dry-fire sequence while watching for the hammer's rear-most position.

Notice?

The hammer doesn't go back as far during the DA stroke. The difference is startling, enough so that locktime is reduced and these guns actually have more theoretical accuracy on tap in DA mode than SA, believe it or not. That's assuming you have a GOOD smooth DA trigger of course, allowing you to use that extra "theoretical accuracy".

 

[Ben Shepherd]

Remember, most 454 loads use rifle primers. They have harder cups than pistol primers.

You do not want to screw around with putting in lighter springs, lightening the hammer, etc., unless you are willing to go through the time and expence of testing your rounds for reliability before you depend on them.

This can be an expensive/painful proposition in this caliber.

 

[Cthulhu]

First, thanks to Jim and Ben for your response.

I'm familiar with the mechanics of double action revolvers, and I pointed out the same thing about hammer travel. He is convinced that all hunting is done using single action. Since we are both gunshop employees and thus unparalleled experts in every aspect and application of firearms, I (a part-timer, and, therefore, inherently less knowledgable )am not going to try to convince him otherwise. As far as I can recall, locktime never caused me to miss a shot on game with my Bisley Blackhawk .45 Colt. With lightened main springs and a power custom hammer, that Blackhawk should have longer time from trigger squeeze to primer pop than anything else.

I don't see how hogging material out of the hammer would effect reliability, even on rifle primers.

Lightened hammers powered by the same available amount of energy from the main spring will, ceteris paribus, have increased angular and tangential velocity versus the stock hammer. This translates to both higher momentum and kinetic energy of the firing pin, as well as shorter time of flight for both the hammer and firing pin. I have lots of really dreadful calculations that led me to this conclusion if someone wishes to throw down the gauntlet, but I"ll sadden the other mechanical engineers reading this post by not including them here. The physics seem pretty solid.

Since he is trying to reduce lock time, not necessarily lighten the trigger let-off in DA or SA, putting in lighter springs would be counterproductive, as would messing with the transfer bar assembly.
What I'm curious is if lightening the hammer will weaken it enough to cause premature failure, or effect the other characteristics of the gun (function of the transfer bar? Primer flow?) Basically a reason he should not get a SRH, order a spare hammer, give it a good polish and start milling away?

WildAlaska? DE50?

 

[protozo1]

On paper the calculations I'm sure are wonderful but I have to agree the polish job seems the place to start. Removal of friction would seem a bigger factor than removal of mass in this situation. Once that has been done than the gains your calcs. are showing you will be more apt to be achieved if you still choose to go that way.

 

[Stainz]

I have seen some poorly cast transfer bars, such as my most recent new purchase, a SBH (.44M). A few minutes with a diamond file & stone left it's face properly flat & shiney. I am afraid that the cast bar may not have been up to the repeated impact of the higher KE of a lightened and faster hammer, although the momentum transfer may have been nearly the same. As to re-bearing a SRH hammer pin, I won't... unless the hole gets elongated. My 7.5" SRH is my first DA revolver - and it 'broke-in' quite well, especially DA - my preferred method of shooting, albeit problematic when you switch from a RH/SRH or S&W to a BH/Vaquero, etc.

I tried lighter springs in my SRH - but a few 'clicks' when I expected 'booms' caused a quick return to the OEM springs. Those 'clicks' did come from commercial .454 rounds (Fresh Hornady 240gr 2,000 fps XTP's.), my very light (.45 Colt cowboy-ish) reloads actually employed small pistol primers (not reccomended!) and were quite reliable with the lighter springs. The stock springs placed my broken-in (by lube & dry firing...) as my standard, not eclipsed in DA until I broke in a new S&W 625 Mountain Gun in .45 Colt. That SRH still rates quite highly, slightly better than my new RH in .45 Colt, but not as good as several of my S&W's (Life was simpler when I had only that SRH and a BH!).

I would leave the springs as is, break it in, and learn to lead and fire DA. It is a well-engineered revolver 'as is'.

Stainz

 

[Cthulhu]

I thought I would let this post stew for awhile and rack up more views/comments.

Stainz, your info on the cast transfer bars possibly cracking is exactly what I was looking for.

Protozo1, I'm not sure what your post was trying to tell me other than to inspire distrust in my calculations. Would you care to offer a theory of how reduction of friction will speed the locktime of the falling hammer to a greater degree than removal of mass? Even without formal calculations to back it up, I would be interested.

To the other posters who would rather skim my posts instead of reading them, I'll summerize to five points/ questions.

1. Reducing Locktime is not my idea. It is a co-workers.
2. The goal is to reduce locktime in single action. Not reduce trigger pull weight, travel, double action pull, etc.
3. Reducing spring force is counter-intuitive (and mathematically unsound), and I never advocated that I wish to reduce the power of the springs.
If anything, I making the springs stronger would improve KE/Momentum and reduce time of flight of the hammer.
4. What are the possibilities of failure in reducing the weight of the hammer, strengthening the springs (somehow) or both?
5. Has anyone else tried this?

 

[JohnK]

Can he already shoot more accurately than the gun is capable of? If not he's not going to see any benifit from reducing the lock time.

In theory a gun with a faster lock time would be more accurate. In practice I doubt 1 in 100 shooters are accurate enough to tell the difference, especially in a hunting scenario. If at all possible he should be using something as a rest when hunting anyway (tree, rock, pack etc) and not trying to take off hand shots unless there's no other option.

 

[JohnKSa]

JohnK took the words out of my mouth.

If he's shooting offhand with a revolver at a live target and thinks that locktime is a significant variable then:

1. I should immediately recognize his name from his long career in exhibition shooting.

OR

2. I should immediately recognize his name from seeing it come up repeatedly in his many wins and near wins of the Bianchi Cup.

OR

3. He's messing with you--after having put the million or so rounds downrange to attain the level of proficiency required to truthfully make such a statement, he's also learned enough about gunsmithing to know the answer without asking you.

OR

4. He doesn't have a clue about how infinitesimal the increments of time are that he's talking about nor what kind of effect it's going to have on his practical accuracy.

 

[Wildalaska]

We domnt lighten hammers, no need...

WildmetalcuttingmavenAlaska

 

[Cthulhu]

I would vote for number 4 in this case. He is knowledgable about firearms in general, but his whole point is based on his experience with decreasing locktime on precision rifles. Apples to oranges I know, but he thinks it is too long, and that shorter is better.

I have personally taken game with no problems using a Blackhawk, Sharps, Military Mauser, Mosin Nagant, Marlin Lever gun, etc. All of which have dismal locktime compared to, say, a Rem 700. If I missed, it wasn't due to muzzle wavering minutely while I waited for the hammer to fall.

Whether or not it is practical or worth worrying about or if he has the skill to take advantage of it is immaterial in this case. 99% of firearms are capable of outshooting their operators dead stock. Its his gun (or will be).
He wants to reduce locktime. Hogging material out the hammer and/or strengthening the springs will reduce locktime, because math tells us (most of us, at least) that it will. Any other mechanical reason that this should not be done?

 

[pauli]

here's one: the poor little ruger revolver might not stand up to the beating! er...

actually... the more energy in the hammer, the more energy goes into the transfer bar. the more energy in the transfer bar, the more energy in the firing pin. the more energy in the firing pin, the harder the primer strike. go too far, and his OMGSHORT locktime is going to turn into a rather surprising jet of gas through the back of the gun...

 

[Cthulhu]

Thanks Pauli.

Wildalaska, I thought I saw a Wild West-chopped SRH with bobbed hammer in an earlier posting. Any problems resulting from that?

 

[Wildalaska]

Ya know we do so many of them Im gonna have to look! I think we tried lightening one, but the rest are all standard (I thinK)..holy skidmarks batman, I dont even know what our own stock loooks like ROTF

WilddazedandconfusedAlaska

 

[Cthulhu]

Thought I would chime in with a follow up. Going against the advice of most in this thread, the hammer was given a "speed slot" by a gunsmith and his trusty vertical mill. The slotting was very well done and looks like a factory mod. Going against my advice, lighter springs were installed at the same time.
The results?
The newly lightened hammer with lightened springs failed to ignite the primers 100% of the time,with all ammo tested, in either DA or SA mode. This confirmed my calculations and thoughts on light springs.

After replacing the light springs with factory springs, all ammo tested ignited 100% of the time. The hammer fall is noticibly faster and, most importantly, fast enough for the gun's owner to convince him it was worth the trouble. This was done in Sept 04, and has successfully held up to regular firing of .454 ammo. Admittedly, not a torture test, but it is likely the slotted hammer will have fairly long life on a handgun hunter's revolver.

Lessons learned:

-Ruger SRH hammers are really hard! Milling them is not easy without the correct bits. Go Carbide!

-The lightened hammer with factory springs still has sufficient juice to pop factory ammo.

-Mathematics can occasionally correctly model the outcome of real-life events. This was a freak occurrence and it should not be praised, exaulted, referenced, ballyhooed, or even discussed in front of anyone, particularly children.

-Durability of the hammer, transfer bar, or firing pin has not been affected (thus far).

-Ruger, as of this writing, will not sell you (or me or anyone else) a hammer. It is considered a factory fitted part and will only replace them if they fail. Keep this in mind before you chuck your hammer into the mill. They might have a hard time believing that the large hole in the hammer was an overlooked factory defect.