The strangest thing happened to my B50

[GarthThomas]

I made a new hammer from Nylatron GS which I think is the same as Nylon MD and when I installed it I used the original BAM hammer spring. I haven't checked it on the Chrony yet but it sounds hot enough the thing is the sound it makes as far as resonance from the spring when cocking and firing is quite loud and different, its not the same ping as before.
The strangest part is it went from a one holer with Crosman Premier 7.9 Domes to terrible and some of the other pellets I couldn't use before have now become one holers.
I think I'll take it apart and reassemble to see if there was something in that process that caused the change. Otherwise I think its getting more shots per fill but I should have Chronied first I know.

[Taso1000]

Hi Garth,

The mass of the original steel hammer may have been dampening the sound.  Also the steel hammer accelerated slower than the now much lighter nylon hammer with the same spring.

Your velocities should be faster and you also changed the harmonics of the system and moved the old sweet spot to a new sweet spot.

Maybe if you bring the velocities back down to what it was before your accuracy may improve. 

You'll figure it out I'm sure.   

I need to startup tinkering with my projects again.   

Taso

[GarthThomas]

I think I pinched a TP o-ring and twisted something torquing it together the first time, so when I re-assembled it was business as usual.  I was getting 19fpe with CP ultra mags and as little preload as I could manage on the factory spring and a smaller TP but I think its using less air. I'm trying to figure out a way to make one of those SSGs without doing anything irreversible.

[Motorhead]

MAJOR change in valve dwell happened !!!
With the Substantially Lighter hammer under the same spring energy valve is striking poppet lifting it off it's seat a lot faster !!
Lack of hammer weight allows valve to change direction and get closed faster too !

In the 6-8 BAM-50's i tuned a few years ago when using a light hammer you needed to swap out the poppet spring in valve to one lighter as well.  * What your doing with a Light hammer of solid Nylon is best used along with a regulator.

Not sure on 3K within valve that alight hammer can give any sort of decent shot string over but a VERY NARROW pressure range that I guess being closer to @ 2K than 3K

JMO ....

[Taso1000]

Garth,

Reach out to David (Rocker1).  He has made them for the B50's. 

I think the new twin spring style may be easier to make.  I need to read through those TSS threads again for construction ideas.

Taso

[Taso1000]

Garth,

I totally forgot.  SSG's and TSS's are pretty much unnecessary with lightweight hammers.  The hammers retain so little energy after their initial impact that there's not enough remaining momentum to crack open the valve again.

Taso

[GarthThomas]

Thanks for the replies, I have done some valve work in the past short of changing the spring which I haven't been able to source up here, reduce the washer thickness and taper the valve stem. I posted in that SSG sticky my new SSG but of course as usual I'm trying to copy others with out knowing how things work, so far I've ended up with a neat little thing I can use to turn the power up and down and I haven't made irreversible changes. In fact I'm testing it out of the stock so I don't have to cut a notch for the rod yet

[rsterne]

Did you vent the space behind the hammer?.... See my post in the SSG thread above....

Bob

[Taso1000]

Garth,

I vented mine like this:

http://www.gatewaytoairguns.org/GTA/index.php?topic=99648.60

Next one I do I will do a little different.  I like where the output exits from the circumference and is above the trigger mount and almost invisible but I wrecked the spring pocket.  So maybe a smaller diameter hole that is more parallel to the bore line.

Taso

[GarthThomas]

I'm working up the courage to drill a hole but I'm thinking I'll drill the tube right beside the trigger housing and just before the edge of the end cap where its inserted.
The spring pocket on mine has a spring guide and preload washers so doing like you or Motorhead won't work. I had previously enlarge the diameter of the spring pocket for the MC spring so the factory spring was a little snaky especially once it was preloaded for the SSG.
]

[GarthThomas]

Taso I finally finished reading your Regulator post, wow is all I can say, that is an education. Thanks!

[Taso1000]

Garth,

Thank you.  I jumped into the deep end with that project.  lol  But it wouldn't have been possible without the help of GTA members. 

Will you be drilling through the main tube and through the trigger housing?  I think that may blow crud onto the trigger components.

I just thought of something when I looked at a B51 action.

What about a notch at 6 o'clock of the rear cap front to back?  You could hide the notch like I did over the rear trigger housing?

Thanks,

Taso

[GarthThomas]

That's a good idea, I ventilated the heck out of the hammer so I'm going to start shooting for now, the problem I have is I can't make my mind up on how I want it to shoot. Right now it's inside of course so I'll settle for 12fpe or less, most likely less. I was noticing how little a turn of the screw affects velocity. I was thinking of a reg. as well but then the part about not being able to make up my mind kicked in so I'll save the money for now.
Your right about the members here, I haven't found a forum to compare with the volume of knowledge and the willingness to help that exists here.

[Taso1000]

Garth,

I have that dilemma too about how to set the rifles up.  Accuracy first and power second.  I was thinking one B51 shooting the lightweight .177 pellets between 800 - 900 fps. Another B51 shooting the heavy .177 pellets and Piledrivers between 800 - 900 fps.  And then a B51 shooting the 34 grain JSB Jumbo Beasts between 800 - 900 fps.  They'll all be regulated.

Since I got the Air Arms T200 I really don't need a low power B51 .177 rifle.  There's no point to a low power .22 in my opinion.

I got the hammer springs from Menards that seem to have the right spring rate.  I've never made an adjuster.  I just clip coils or add washers in the end cap spring pocket to adjust.

Thanks,

Taso