Tapco Gas Puck

[nate77 0]

[Lone Star Arms 2,047]

[Cobra 76 two 2,677]

What setting did you have the plug adjusted to and did you try changing it with the tapco puck in there?

 

[nate77 0]

My gun is pretty new and marginally under gassed so I went straight for setting 3 with federal #6 1290fps Game Loads. I also tried setting 2 and one more full counter clockwise revolution at setting 3; nothing made a difference.

 

With the stock puck, the gunfixer runs the same Federal on setting 3, and Estate 1 1/4oz high velocity high brass on setting 2.

 

Anyways, if anyone has had a different experience with the Tapco let us know.

[sapper1371usmc 107]

My S12 functions as good as or better with the Twisterpuc Standard, hates the medium, never tried the magnum.

[nate77 0]

My S12 functions as good as or better with the Twisterpuc Standard, hates the medium, never tried the magnum.

 

Thanks, I plan to try the standard Twister puck next, hopefully it will put my gun over the top, and make is 100% reliable with Federal bulk ammo.

[Lone Star Arms 2,047]

Nate, after reading your post I took measurements of the Tapco puck, and it is virtually identical to the factory puck. There is a very slight difference in weight with the Tapco puck being a couple of grams lighter. This is no doubt due to the fact that the Tapco puck is machined from US tool steel rather than whatever it is that the Russians use (which appears to be incredibly dense, cold forged, military grade tool steel).

 

However, beyond the slight weight difference I find no physical reason that the Tapco puck should perform differently from a factory puck of exactly the same dimensions. I will test one in several guns when I finish and test fire the latest run of custom guns, and report my findings.

 

Thanks for posting this topic!

 

Michael Rogers

Lone Star Arms

[Mullet Man 2,114]

LSA, how would the weight affect the cycling of the action?

Would it slow it down because of not enough mass and inertia/momentum behind it compared to the stocker?

[Lone Star Arms 2,047]

LSA, how would the weight affect the cycling of the action?

Would it slow it down because of not enough mass and inertia/momentum behind it compared to the stocker?

 

Actually, the puck is heavy enough, and close enough in weight where the weight difference shouldn't be an issue. If I recall correctly (I'll double check tomorrow) the factory puck was in the neighborhood of 39 grams and the Tapco just north of 37. I believe both weigh well over a troy ounce (once again, I need to double check this), and fit the chamber with almost no tolerance to spare.

 

My guess, is no difference in performance, but I will need to do a range test with the Tapco and factory puck in several guns just to be absolutely certain one way or the other.

 

The tool steel in the Tapco puck appears to be slightly softer but appears to be plenty hard nonetheless, and unless there is deformation with use, I don't see an issue from that perspective.

 

I have long been of the opinion that a US puck is great if you need one for a compliance part, but don't believe they have any significant effect on performance one way or the other as long as they are the correct size and diameter.

 

In fact it has occurred to me that if a gun were truly over gassed, reducing the diameter of the puck just a hair could help correct the issue without resorting to pulling the block off and filling vents in the barrel.

[nate77 0]

Nate, after reading your post I took measurements of the Tapco puck, and it is virtually identical to the factory puck. There is a very slight difference in weight with the Tapco puck being a couple of grams lighter. This is no doubt due to the fact that the Tapco puck is machined from US tool steel rather than whatever it is that the Russians use (which appears to be incredibly dense, cold forged, military grade tool steel).

 

However, beyond the slight weight difference I find no physical reason that the Tapco puck should perform differently from a factory puck of exactly the same dimensions. I will test one in several guns when I finish and test fire the latest run of custom guns, and report my findings.

 

Thanks for posting this topic!

 

Michael Rogers

Lone Star Arms

 

Thanks for the size clarification I don't have any precsion measureing device.

 

Does your Tapco puck have rounded edges like mine, maybe that could be part of the problem.

 

Anyways, I have a twisterpuc on the way, so maybe this weekend, I can take the twister, tapco, and stock pucks out and give them each a run. I'll also try them each with the stock and Gunfixer plugs.

 

I'll report back after the test.

 

Thanks agian.

[Lone Star Arms 2,047]

Nate, after reading your post I took measurements of the Tapco puck, and it is virtually identical to the factory puck. There is a very slight difference in weight with the Tapco puck being a couple of grams lighter. This is no doubt due to the fact that the Tapco puck is machined from US tool steel rather than whatever it is that the Russians use (which appears to be incredibly dense, cold forged, military grade tool steel).

 

However, beyond the slight weight difference I find no physical reason that the Tapco puck should perform differently from a factory puck of exactly the same dimensions. I will test one in several guns when I finish and test fire the latest run of custom guns, and report my findings.

 

Thanks for posting this topic!

 

Michael Rogers

Lone Star Arms

 

Thanks for the size clarification I don't have any precsion measureing device.

 

Does your Tapco puck have rounded edges like mine, maybe that could be part of the problem.

 

Anyways, I have a twisterpuc on the way, so maybe this weekend, I can take the twister, tapco, and stock pucks out and give them each a run. I'll also try them each with the stock and Gunfixer plugs.

 

I'll report back after the test.

 

Thanks agian.

 

Nate. The Tapco pistons I have do not have rounded edges. They are the same size and shape as the factory piston. I did compare weights again when I arrived at the workshop. The factory piston came in at 37.1 grams, and the Tapco at 36.8 grams, a difference of only .3 grams or 1%. So the weight difference is not as significant as my recollection, and certainly not significant enough to affect performance

 

I'll know more after the next range test, will post results and may even use video to document the findings.

 

Best of luck with your tests!

[skiboatsp 111]

LSA, how would the weight affect the cycling of the action?

Would it slow it down because of not enough mass and inertia/momentum behind it compared to the stocker?

 

Actually, the puck is heavy enough, and close enough in weight where the weight difference shouldn't be an issue. If I recall correctly (I'll double check tomorrow) the factory puck was in the neighborhood of 39 grams and the Tapco just north of 37. I believe both weigh well over a troy ounce (once again, I need to double check this), and fit the chamber with almost no tolerance to spare.

 

My guess, is no difference in performance, but I will need to do a range test with the Tapco and factory puck in several guns just to be absolutely certain one way or the other.

 

The tool steel in the Tapco puck appears to be slightly softer but appears to be plenty hard nonetheless, and unless there is deformation with use, I don't see an issue from that perspective.

 

I have long been of the opinion that a US puck is great if you need one for a compliance part, but don't believe they have any significant effect on performance one way or the other as long as they are the correct size and diameter.

 

In fact it has occurred to me that if a gun were truly over gassed, reducing the diameter of the puck just a hair could help correct the issue without resorting to pulling the block off and filling vents in the barrel.

 

Just measured on Ohaus triple beams 37grams

 

The mass should have little effect as I am using tappets with 1/2 that weight.

 

The shop who ran the tapco tappet is right around the corner from me. I will talk to him about the specs.

[ErikTaylor 41]

 

Good post - and it brings up an important issue. If the Tapco puck is even slightly smaller in diameter than the factory puck, it is going to allow gas to escape around the edges and that is going to have exactly the effect you described. Having a good tight seal within the gas chamber is key to optimum performance.

 

The idea of a puck that keeps the gas chamber clean is attractive, however if the cost of doing so is the loss of linear force, what advantage is there to using a twister puck over a slightly undersized Tapco puck?

 

As I generally use factory pistons in my own builds, I am interested in learning from others using US made pistons from different sources what their experience has been with the particular US made piston they are using.

 

That makes a shit ton of sense. I'm going to put the stock puck back in and see if that makes a difference, because I currently have the twister puck in mine.

[skiboatsp 111]

 

Good post - and it brings up an important issue. If the Tapco puck is even slightly smaller in diameter than the factory puck, it is going to allow gas to escape around the edges and that is going to have exactly the effect you described. Having a good tight seal within the gas chamber is key to optimum performance.

 

 

 

 

 

The idea of a puck that keeps the gas chamber clean is attractive, however if the cost of doing so is the loss of linear force, what advantage is there to using a twister puck over a slightly undersized Tapco puck?

 

As I generally use factory pistons in my own builds, I am interested in learning from others using US made pistons from different sources what their experience has been with the particular US made piston they are using.

 

That makes a shit ton of sense. I'm going to put the stock puck back in and see if that makes a difference, because I currently have the twister puck in mine.

 

 

The slanted grooves are not meant to spin the plug just act as shear surfaces to clean built up fouling

 

There are no relieve cuts or angles on the edges that would allow the tappet to damage the chamber.

 

Look at an end mill or milling cutter and you can see how the tappet cannot cut the bore and probably does not spin at all.

 

I believe it's a great idea!!

Edited March 4, 2010 by saigatechusa

[nate77 0]

[Lone Star Arms 2,047]

[Lucas_061287 0]

Not to derail the thread, but what about the Chaos puck?