M1/M14 Speedhammer

So why can't you just go out and buy one? This one weighs 63% of a regular hammer and has thousands of cycles on it so far. It's ugly, but it has been on several diets to get to this point. I think there MAY be a bit more that could go, the web is at 0.090" now. This is a commercial CAST hammer, BTW!

I think its an idea worth manufacturing, so be my guest! Just remember it was plastered here first!

https://www.milsurps.com/images/impo...DSC01660-1.jpg

https://www.milsurps.com/images/impo...DSC01661-1.jpg

https://www.milsurps.com/images/impo...DSC01662-1.jpg

https://www.milsurps.com/images/impo...DSC01663-1.jpg

https://www.milsurps.com/images/impo...DSC01664-1.jpg

https://www.milsurps.com/images/impo...DSC01665-1.jpg



Also, another "modded" part thrown in:

https://www.milsurps.com/images/impo...DSC01666-1.jpg

So how much does it lighten the rifle?

I was thinking the lightened hammer is more for improved locktime and less "jarring" on impact than for absolute weight reduction. There's plenty of Lightened hammers available for ARs, never mind 1911 pistols. Its more an accuracy mod than anything.

The trigger housing cuts only pulled out a few ounces, but they add up if its done in enough places. The housing mod was originally done by Springfield (the Government run one) during the development of the M14. I saw a pic and went from there.

I'm really stretching to remember. I can't remember who it was that tried this but someone did some work in this area with regard to the Garand - whether it was the Air Force guys (that rings a bell) or the fellas at Springfield Armory themselves - but one of the match conditioning teams tried to improve lock time by lightening the hammers.

If I recall correctly, there was no discernable improvement so they did not continue with the idea (as it was a considerable amount of work). Scratching my gray matter to remember where this was written but I think it might have been Kuhnhausen (??), or maybe, ... dunno.

Really cool hammer though ... nice job.

Couldn't one make their own speedhammer by drilling holes through the side, taking care to ensure said hole(s) aren't too close to where the hammer strikes the firing pin? If a cast hammer as shown can hold up it seems that a forged hammer could stand to have holes through it. I'm not a metallurgist or engineer so this is just a WAG.

Interesting idea. As the hammer is rotating on a pin, what counts is to reduce its Moment of Intertia, more than just its weight. Moment of Inertia is in rotational motion what ordinary mass is in linear motion. The quirky thing about rotation is that not all mass is created equal. The further away you get from the pivot point, the stronger contribution a bit of mass makes to the Moment. It is really just a matter of leverage. So if you remove a mg of hammer mass 20mm away from the pivot point, it will have a 5 times greater effect than a bit of mass removed only 4mm away. If it's true that the lightened hammer does not reduce lockup much, one reason might be that up at the top, around the hooks and camming lug, where it counts the most, it isn't possible to remove much material. Cool picture though.

Understand about moments, went a got a degree in mechanical engineering, which I promptly never used upon graduation. The mass at the periphery was left to maintain functional interaction w/o getting too experimental. I have no quantitative measurements, but I like it! If you want to get more scientific, I'd be interested in your ideas in how you would measure improvements.

A few on going notes on this test piece-

Some recent primer hits. Hammer still popping them nicely!

https://www.milsurps.com/images/impo...stuff038-1.jpg

https://www.milsurps.com/images/impo...tuff0351-1.jpg

Regular old GI hammer spring, BTW.

https://www.milsurps.com/images/impo...stuff027-1.jpg

https://www.milsurps.com/images/impo...stuff029-1.jpg
AND TRW GI barrel. Chrome's not doing well, but...

Shot this 5 round group today, so it doesn't seem to hurt ignition or disturb the rifle on impact:

https://www.milsurps.com/images/impo...stuff040-1.jpg

way too many words with multipul sylibles,your killing me.

We where talking about this a few months back when discussing some of John Garand's comments about improving lock time in the M1. There is a little room for improvement in the hammer spring as well.

Progress on the Mk.II hammer, which may be news to those on this forum. A friend is EDM'ing what will hopefully will be a somewhat more efficient design. The process has not been without drama, and the photo below will show a few "boo-boos".

https://www.milsurps.com/images/impo..._8590mod-1.jpg

What's really exciting is that another fellow has made ten or so of a different design, AND has a 10,000 frames per second camera which shows the improvements in speed. His first effort resulted in a 20% reduction in locktime, which is not bad at all! Puts it in the 6ms range, about like a M1903 Springfield.

Thare's also a very good highpower competitor who has agreed to try them in his service rifle(s). So some unbiased field reports may be forthcoming in the next year.

Now in hand, a few more shots before polishing and further mods.:

https://www.milsurps.com/images/impo...tuff0031-1.jpg

https://www.milsurps.com/images/impo...tuff0021-1.jpg

https://www.milsurps.com/images/impo...tuff0081-2.jpg

https://www.milsurps.com/images/impo...tuff0061-1.jpg

Current weight is 399 grains, about 52% of what is standard.

Well, the Mk.II Mod.1 has already supplanted the Mod.0 shown above.

https://www.milsurps.com/images/impo...stuff008-1.jpg
https://www.milsurps.com/images/impo...stuff007-1.jpg
https://www.milsurps.com/images/impo...stuff003-1.jpg
https://www.milsurps.com/images/impo...tuff0121-1.jpg

As soon as it's function tested it'll be off to a photo lab shoot with a 10.000 frames per second digital video camera, and then off to a High Master highpower competitor for extended trials.

It's a "one-off" prototype, but there's an alternate design starting in limited production that ought to be available for sale early in 2012, thanks to the efforts of a fellow enthusaist and businessman who already does optically enhanced rear peep sights for Garands and M14/M1A platforms..

Art Neergaard (Shootingsight.com) maker of rectangular apertures and other goodies marketing an adjustable trigger for M1 Garand and has a "speed hammer" in development. Good guy, quality stuff.

Tom

Yah, he's having 7,62mm Firearms do him up some new. We've been going back and forth a bit on another site. I've been running one of his hammers for over a month. His are running on the heavier side, but they were just a "proof of concept" batch done up for testing. The high master high power shooter/guinea pig has been running on of his with one leg broken off for several weeks with good success. The new batch should have Art's design refined to eliminate the weakness in the RH leg.

Art is also going to do the high speed photographry mentioned above. It's not like we're in competition or anything, more of a long distance collaborative effort.

---------- Post added at 01:33 AM ---------- Previous post was at 01:30 AM ----------

BTW, I've gotten one down to 314gr as of 17 December but it's not suitable for general usage, as it no longer has a hammer nose extention or overtravel stop surface. It's for testing the limits of primer ignition.

An earlier test of a stock and an Art7 Mk.I test hammer is shown in the you tube video below. . I forget the exact weight, but it's in the 400gr range resulting in a 20% improvemnt in speed. Stock is about 770gr. The jm Mk.II mod.1 is in the 385gr weight range, but the next ones may be a little less.

http://www.youtube.com/watch?v=GbxpU...ature=youtu.be

---------- Post added at 02:21 AM ---------- Previous post was at 02:12 AM ----------

Some old numbers:

USGI (-2 SA) hammer: 769 grains/ 1.8oz. 100%
USGI D5546008 hammer with one sear leg missing: 747gn/ 1.7oz. 97%
art7 Mk.I hammer: 520gn/ 1.2oz. ~68%
art7 Mk.I hammer mod. 1: 490gn/ 1.1oz. ~64%--This is one of Art's early EDM'ed hammers after polishing and some further minor lightening cuts.
jmoore Mk.I hammer: 485gn/ 1.1oz. 63%
jm Mk.II Mod.1 hammer: 356.5gn

"As delivered" Art7 Mk.I hammer for testing:

https://www.milsurps.com/images/impo...stuff021-1.jpg

Modded Art7 Mk.I hammer:
https://www.milsurps.com/images/impo...tuff0045-1.jpg
https://www.milsurps.com/images/impo...tuff0063-1.jpg

His new hammers should have the web modified somewhat as below:
https://www.milsurps.com/images/impo...uff01621-1.jpg

Whislt on the subject of speed, these hammer spring plungers weigh right at 1/2 original weight:
https://www.milsurps.com/images/impo...stuff017-1.jpg

That's some fancy machine work. Looks nice. Sounds like it's as fast as an Extreme or Geiselle trigger in an AR. I asked him awhile ago about a striker design for an AR (which would be the only way to go to get close to bolt gun lock time) haven't heard any updates on that. He and Bill Geiselle have taken an AR trigger as far as possible I'd say. There aren't any durability issues so far? Or have they been worked out?

Tom

The old one keeps running just fine. The new ones are too new to know how they'll hold up over many thousands of rounds (and dry fires.) It's still in the experimental and trial production phase. But the results have been quite encouraging. Hopefully, there will be much more progress next year as more of them get into the system.

Some updates:

The jm Mk.II Mod.0 was sacrificed as a general purpose hammer to become a "how light can we go" test piece. At the current weight of 234.5 grains it has been clocked at 4.8 milliseconds locktime. Compared to the stock 769gn hammer at 8.2ms. Primers are indented as deeply and more crisply than ever!

The Mk.II Mod.1 was clocked at 6.2ms. It's starting service in an active NRA high power shooter's rifle this year for extended trials.

The "Hammer of Insanity" Mk.II Mod.0"test":

https://www.milsurps.com/images/impo...tuff0142-1.jpg

https://www.milsurps.com/images/impo...tuff0101-1.jpg

https://www.milsurps.com/images/impo...tuff0351-1.jpg

https://www.milsurps.com/images/impo...uff00821-1.jpg

The old Mk.I Mod.0 has morphed into the Mk.I Mod.1, but not without a visual drama:

https://www.milsurps.com/images/impo...stuff036-1.jpg

https://www.milsurps.com/images/impo...stuff035-1.jpg
The hole was unintentional. It was a small breakout that's been blended to it's current size. Ugly, but shouldn't hurt anything.
Currently at 363 grains, but there will be some more coming off. It has run for years at 480 some odd grains, but it's time for further mods.

Plenty of cosmetic cleanup and durability polishing to go, too!