Full Results Posted: MDS Nylon Hammer in 22XX

[imadunatic]

I'm thinking it would need to be a steel/mds nylon hybrid hammer in order to get anywhere near the right mass since this is only a .750" diameter, but I'm wondering if anyone else has played with it. 3/4" MDS nylon is dirt cheap and easy to machine, seems like it might be a good winter experiment.

Results here: http://www.gatewaytoairguns.org/GTA/index.php?topic=120356.msg1190924#msg1190924

[rsterne]

You might find that the trigger sear in a 22XX will damage the Nylon hammer.... They are mostly being used with the MRod and PRod triggers which have a drop sear design....

Bob

[imadunatic]

You might find that the trigger sear in a 22XX will damage the Nylon hammer.... They are mostly being used with the MRod and PRod triggers which have a drop sear design....

Bob

Bob,

That's the next stage in my 2240 build, was going to buy a PRod hammer at the same time, but then thought as long as I'm replacing the hammer, why not try a MDS Nylon hammer. I can buy 5 feet of MDS Nylon for the price of the PRod hammer and it's a labor of love, so that's free. 

But I'm not sold on it yet. Not afraid to be the first, but I like to not waste my time if I can stand on the shoulders of others.

Kevin

[imadunatic]

Well, this is my plan:



Nylon, aluminum, steel and PROD trigger group is all collected. Hoping to get at least a couple of these turned out tomorrow after work.

I also made the spring pocket 1/2" deeper to allow for a longer spring; which should help with fitting the internal SSG and reduced cocking effort. I'll post my findings once I have something concrete. I also plan on fitting one of these to my 2400 HPA conversion; whichever proves to be the best balance of cocking effort, efficiency and power for that platform.

[Bob Pratl]

Kevin, I also just started upgrading my 2240 and was considering replacing the hammer with MDS/steel one when I came across your posting. Great
Keep me informed on your progress as I'm confused on the best weight for the MDS hammer. I would like to setup for 600 fps & KE~14.  I have already replaced the trigger group with the Prod assembly which is a massive improvement. Bob

[imadunatic]

Still need to sand the edges and hoping to get some testing done today or tomorrow, but none the less the three kings are done:



I didn't end up putting the set screw in the aluminum or steel as that was more for a hard striking surface rather than adjustability. But we all know how these things evolve.

They did end up slightly lighter than anticipated due to the on the fly engineering change, but they still tip the scales at 10grams, 13 grams and 26 grams.

[Hobbyman2007]

Looking forward to the testing . Do you plan on using this on co2? Either way should gain a bunch of shots ,hopefully you won't need too much spring and make cocking a pain .

[mr007s]

Whats the plan for keeping the cocking pin secured?

[imadunatic]

Looking forward to the testing . Do you plan on using this on co2? Either way should gain a bunch of shots ,hopefully you won't need too much spring and make cocking a pain .

Yep, this is staying on CO2. Unfortunately it's cold this time of year (including my basement, which typically runs in the 50's during winter), but it should give some decent data for efficiency differences between the 3 hammers.

I'm a big fan of comfort, so cocking effort will definitely be one of the big three decision makers for these hammers (the others being power and efficiency of course).

My gut feeling is that the steel core, nylon outer is going to be the best balance of the three and the major bonus is being able to run it dry so hopefully it helps the consistency as well.

[imadunatic]

Whats the plan for keeping the cocking pin secured?

I didn't change it from a stock hammer. It's just captured in that counterbore between the hammer and the pressure tube.

[Rocker1]

 Most light weight hammers I use are on regulated guns with a much lighter poppit spring, Wish you success in your venture but do think spring pressure will exceed  cocking effort. David

[imadunatic]

Dave,

Nothing ventured, nothing gained! I'll post my findings either way, even if it fails miserably. All in the name of science!

[Bob Pratl]

Kevin, looking good, can't wait to see the results on the 22XX as my MDS stock is waiting in the lathe for machining. I'm guessing that the steel core, 26 gram, hammer will be the winner. Are all of them bored .5" deeper, for a longer spring, as you previously designed ?  Thanks. Bob

[imadunatic]

Are all of them bored .5" deeper, for a longer spring, as you previously designed ?  Thanks. Bob

Bob,

Yes, all the spring pockets are 1" deep. I'm not positive I'll need all that room, as I've been able to compact my final SSG immensely even with the stock hammer, but I don't think it will hurt. Worst case, I've made some spacers for this pocket so I can play with that if needed.

This was my machining print:



Only major change was the OD needed to be .740"ish to really slide easy in the tube. The stock hammer measures .738"ish.

[Bob Pratl]

Great, thanks for the update and hammer drawings, this will save me a lot of time. Bob

[fivestar45]

Looking forward to seeing how these play out. With a standard design valve and striker spring I think that you might come up a bit short on both lift and duration. If you up the striker spring to compensate, I think that cocking effort will get heavy. Not because of your better fitting, slippery strikers but rather from the short 1/4" bolt side loading into the breech bore. So if you like smooth, easy cocking you might want to take a look for some improvement in that direction.
Now..what I think would be real interesting would be seeing you pair up those light strikers with a Don Cothran valve...Not much striker mass, or spring required for those...especially running on co2.

[imadunatic]

Well, unfortunately I can't complete testing today because the cocking pin holes on the aluminum and the steel hybrid hammers is too loose to function. The cocking pin actually "cocks" in the hole and locks the hammer in place. I'm guessing when I drilled into the aluminum and steel the drill wobbled slightly and opened it up. I'll rotate the hammers tomorrow, drill an undersize hole then actually ream it to 1/8". If that doesn't want to work, then I'm building a custom cocking pin that is longer so that it can't cock quite as easily (will most likely do that anyways, especially since the results of the Nylon hammer lead me to believe that is what I'm going to run!).

Summary: The nylon hammer was able to make almost 100 FPE more than the stock hammer from one powerlet with only slightly more spring pressure/cocking effort (I can't measure this, but it's still very very low).

Temp in the basement is at 56 degrees so I'm positive one could use a heavier pellet on a hot summer day, drop the average FPS and stretch this to the max, but I wanted an apples to apples comparison so I could see the difference between the 2, not an all out, "can I begin to approach Bob's magical 600 FPE from one powerlet".
Stock Hammer total FPE: 324
Nylon Hammer Toal FPE: 420


I'm not sure I'm going to be able to improve upon this, but I'm still going to test it. This goes against everything my gut predicted so I don't even want to speculate what the other hammers are going to do.

None the less, the data:



This is on a stock internals 2240 running a 9.5" barrel and extended (standard discovery bolt probe I believe) bolt probe from Magnum Air Power. I am not going to hot rod this, but I may open it's nostrils slightly to keep the flow of air constantly under compression which may also help with efficiency.

Lastly, having 40 grams less mass moving about in your pistol increases the stability during the shot cycle considerably; this alone is almost enough to make me just go with the ultra light hammer and forget about the other 2. But this is science, and sometimes we press on even if we think we've found the perfect answer.

[imadunatic]

Finally got back to this, and I have to say I'm surprised again. The first time I ran the aluminum hybrid, I thought it might be a fluke because I have never began to approach that many shots, that averaged that velocity from this pistol ever. The second string was actually 2 shots longer than the first, so I don't think that was a fluke. I decided to re-run all hammers today, to help limit variables and I was able to squeeze a little more out of even a stock hammer.

My interpretation is that the results may be flawed in that I used the exact same spring preload for each hammer, I simply increased the gap of the SSG until the velocity was ~420-430 FPS to try and keep the comparisons as close as possible. The reason I believe this may be flawed is that the spring preload and gap I had my SSG set to may just have been the ideal combination that the aluminum hybrid needed. If one were to fully flesh out this investigation I think you would need to play with spring length in order to get the gap close to the same for each hammer to be able to compare apples to apples.

That being said, aluminum string 2 was 463 FPE out of one powerlet and averaged 405 FPS @ 56 Degrees across 88 shots. Only mods to this pistol are a 9.5" barrel from Magnum Air and a discovery probe (slightly extended from stock). This pistol may get some porting just to balance everything, but I feel like I'm going to be hard pressed to gain a whole lot on the efficiency side of this build. 89 "usable" (I stopped at the first shot under 300 FPS) is crazy to me considering the stock pistol did about 420 FPS on it's best day and the shot count was about 35.

I plan to do a similar test in my 2400 HPA conversion, except I fitted the tank block to that last night so it will be an HPA efficiency run over ~25 shots or so.

On to the data (for whatever reason, I can't get my last shot on the best run to graph, it was shot 88, FPS was 285):



Any theories? Discussion? Does this jive with others testing of similar lightweight/no lube hammers? I know Scott has done extensive testing on the Marauder platform, but I couldn't find much data on the 22XX platform. I learned quite a bit and debunked my own as well as others theories.

Overall, to me, this is a win. I have also attached my aggregate results for those so inclined, I do have the raw data available also.

[triggertreat]

Nice long strings you have there.  In regards to the MDS hammer, I am using one from WAR along with his TSS mod and it gives me a much flatter sting in my 22 Synrod than what I get with a SSG and stock weight hammer for sure.  There is absolutely no hammer galling and the cocking could not get any smoother.  I love the MDS hammer.

[rsterne]

Yes, with that spring, the aluminum core hammer seems to be giving you the best efficiency.... and 463 FPE with a 9.5" barrel is pretty decent, for sure.... I did a challenge on the 2240 a year ago.... http://www.gatewaytoairguns.org/GTA/index.php?topic=103343.0 .... the winner got over 400 FPE with a stock 7.5" barrel....

Bob