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View Full Version : The recock: What should stop the motion?



trentdk
10-27-2007, 04:12 AM
So I'm getting back into paintball, I'm trying to tweak my old cocker to be a machine, and I come across this question as I'm timing it: What should be the stopping force for the cocking phase?

Seems that there are three options:
1. The ram hits its full extent
2. The hammer lug hits the body
3. Nothing physically stops it, the force from the LPR pressure pushing the ram piston out is equal to the force required to compress the hammer spring just enough... (1/8inch past the sear, but before the lug hits the body, and before the ram is at full extension)

Mine has been set to #2 for the past 7 years :), which I assume is not correct. I currently have it set as #1, but maybe that is too harsh on the ram? And I don't know if I want to try #3. Am I missing a #4? Thanks :)

wiffle32
10-27-2007, 04:30 AM
Changed my mind... #1 is better than #2... especially if Van says it is.

There are a thousand ways to skin a cat, though.

#3 just sucks though.

k.macocker
10-27-2007, 02:43 PM
def #1..
Kmac

drg
10-27-2007, 07:52 PM
The pump bottoming out, of course :D

wiffle32
10-27-2007, 08:16 PM
The pump bottoming out, of course :D

Yeah that's how I replied at first, but I misread the post and had to go back and edit my response! :rolleyes:

Draken
10-27-2007, 09:06 PM
#3 is great, when you can get it to stay that way, but normaly I set it to #1, ram hitting full extension, I have had to fix bodies that were so hammer lug beat their sear hole was almost 1/8" longer then it started as

Vantrepes
10-27-2007, 10:00 PM
#1, no doubt.
#2 beats the hell out of the body, and #3 ends up being sluggish at the end of the ram stroke.
Rams have bumpers, use them :)
Besides, what do you think is stopping the ram on it's forward stroke? The ram bumpers if you aren't slapping the back block into the body.

trentdk
10-27-2007, 10:43 PM
Besides, what do you think is stopping the ram on it's forward stroke? The ram bumpers if you aren't slapping the back block into the body.
Yep, its that notion that had me leaning towards #1 before asking. Thanks everyone for the clarification!

pintbuster
11-08-2007, 09:48 AM
forgive my ignorance for a moment, but how does one set this up. I am assuming that I would screw the pump arm onto the rams shaft allmost all the way, allowing the ram to fully travel out? Then I would set the cocking rod correctly?
I was under the impression that putting a gap between the backblock and body was possible because the ram was bottoming out in the front. If I set the ram to bottom out in the back, wont the backblock just smack up against the body?

trentdk
11-08-2007, 12:31 PM
Thats where adjustable cocking rods come into play. You need to make the cocking rod long enough so that the ram can fully extend out, even with the small gap between the body and back block.

Railgun
11-08-2007, 05:43 PM
Is there any way to check that without removing the trigger frame?

Wait, I think I just answered my own question as I was typing. WIth the trigger held back so the ram is full back you should still be able to pull the cocking rod back a little before you feel the hammer lug hit the body.
Howzzat?

trentdk
11-08-2007, 07:20 PM
Exactly, and you don't even need to have it aired up. You can check all this with the gun fully assembled and no air.

Here is what should happen when you pull back as far as you can on the back block:
--hear the lug catch the sear
--back block movement stops about 1/8" after that catch
--cocking rod can continue to be pulled even though the back block is stopped by the full extent of the ram.

lew
11-08-2007, 08:56 PM
forgive my ignorance for a moment, but how does one set this up. I am assuming that I would screw the pump arm onto the rams shaft allmost all the way, allowing the ram to fully travel out? Then I would set the cocking rod correctly?
I was under the impression that putting a gap between the backblock and body was possible because the ram was bottoming out in the front. If I set the ram to bottom out in the back, wont the backblock just smack up against the body?


You need to set the cocking rod so the bolt clears the feed neck and allows a ball to feed. I doubt your back block is thick enough to cause the cocking rod limit the ram's travel, so just set everything as normal and it will work out.

I'm not entirely sure what you're getting at when you're talking about setting the ram bottoming out in the back, but all that means is that the ram is reaching its full stroke length as it pushes the bolt back You won't be able to readily modify that distance as it's inherent to the design of the ram.

trentdk
11-11-2007, 12:14 PM
I thought of this last night as I was going to sleep: The cocking rod should not have anything to do with bolt position, ever.

Bolt position should be checked without the cocking rod even being inserted.

Truth: The ram limits travel; the cocking rod does not (if it does, then you're lug-hitting the body). Therefore the cocking rod has nothing to do with bolt position.

Many timing FAQs include info about the cocking rod dealing with the bolt, but that is only an issue IF you're not limiting travel with the ram.

Set the cocking rod long enough to that it is not the limiting factor in the recock, and you're set. (of course if its too long, you wont be pulling the hammer back far enough to catch the sear -- obviously you can't have a 6" cocking rod -- but other wise make it long!)

k.macocker
11-11-2007, 04:42 PM
bingo!!


I thought of this last night as I was going to sleep: The cocking rod should not have anything to do with bolt position, ever.

Bolt position should be checked without the cocking rod even being inserted.

Truth: The ram limits travel; the cocking rod does not (if it does, then you're lug-hitting the body). Therefore the cocking rod has nothing to do with bolt position.

Many timing FAQs include info about the cocking rod dealing with the bolt, but that is only an issue IF you're not limiting travel with the ram.

Set the cocking rod long enough to that it is not the limiting factor in the recock, and you're set. (of course if its too long, you wont be pulling the hammer back far enough to catch the sear -- obviously you can't have a 6" cocking rod -- but other wise make it long!)

Railgun
11-11-2007, 05:48 PM
........I'm not entirely sure what you're getting at when you're talking about setting the ram bottoming out in the back, but all that means is that the ram is reaching its full stroke length as it pushes the bolt back You won't be able to readily modify that distance as it's inherent to the design of the ram.

Lew, you said a mouthful in this one paragraph. But it's not always so cut and dried.

For example, I've got two PB Superbolts. On both the PB rams the travel far exceeds what is needed to move the bolt back the correct amount. The bolt travel in this case being just a hair over 1 inch (call it 1 1/32). But the ram travels more than that by a measured 5/16 inch. A couple of other brand rams I checked are limited to 1 1/16 inch give or take a 1/32 which happens to be the right amount or at least close enough. So in the case of the PB rams there's NO WAY to set up the gun properley where the ram is the limit unless you want some really odd settings. To get around this I swapped rams on one gun but on my other Superbolt I took the ram apart and added a bumper of automotive gas line tubing that I cut 5/16 long. Now both Superbolts are working properley with the ram being the limit and not the hammer lug.

The moral of the story being that if we seem to have trouble setting up the correct back block travel then it may just be the ram travel amount needs to be checked And/or modified if that is possible.

There's another advantage of the ram being the limit as well. We've concentrated on the lug hammering on the body slot but as well as that the back block is taking a hammering due to the sudden stop being caused by the hammer stopping along with the cocking rod. When the cocking rod stops with a thump there's a lot of bending force suddenly being placed on the back block. Over time I could see that working away at the pump rod hole and ovaling it out or at least wearing away at the threading so the pump rod becomes very loose or possibly even breaks away the threaded area from the back block.

This seems like an extremely important setup/timing issue. So far I've based all my setup/timing on the article over at moodypaintball.com and I don't remember this being mentioned. I'll have to double check but if it's not there it would be something to suggest that they add.

lew
11-11-2007, 05:58 PM
Yeah, I was probably drunk when I wrote that. I can't even figure it out now.:rolleyes:

Railgun
11-11-2007, 06:03 PM
Yeah, I was probably drunk when I wrote that. I can't even figure it out now.:rolleyes:

Well... I must have been drunk when I read it because it made great sense to me..... I was complimenting you on your insight buddy! :D

Or perhaps it was just because I had found my own problem related to the ram travel the night before from reading the first part of the thread and checking my 4 cockers.

Vantrepes
11-11-2007, 06:45 PM
It's in there, but not in great detail as to why. That's covered in the other article directly dealing with the cocking rod, and it's settings.. When I wrote the timing article, bolt placement wasn't the fad that it is now, since there were no force feed loaders, or open bolt electros to have problems with them.

Railgun
11-11-2007, 07:58 PM
You wrote up those articles? I doff my mask to you in appreciation. They are clear and easy to follow and helped me a lot with my first cocker setup.

With so much to remember I likely missed the significance of the cocking rod setup as I moved from reading to doing. I probably should have made up a little checklist.

k.macocker
11-12-2007, 01:16 AM
You wrote up those articles? I doff my mask to you in appreciation. They are clear and easy to follow and helped me a lot with my first cocker setup.

With so much to remember I likely missed the significance of the cocking rod setup as I moved from reading to doing. I probably should have made up a little checklist.

you did not know about the infamous vantrepes who is the founder of www.moodypaintball.com ??!!?? What he says about autocockers can be taken as the gospel, despite his past with wiffle.

Kmac

Railgun
11-12-2007, 06:31 AM
you did not know about the infamous vantrepes who is the founder of www.moodypaintball.com ??!!?? ....

rotfl You make it sound like a lead in from an old 50's spy or detective novel.... :D

This October past marks the anniversary of my first year of playing paintball. So there's a LOT of names that don't make connections for me. I've still got a lot of history to learn.

Vantrepes
11-12-2007, 06:45 AM
you did not know about the infamous vantrepes who is the founder of www.moodypaintball.com (http://www.moodypaintball.com) ??!!?? What he says about autocockers can be taken as the gospel, despite his past with wiffle.

Kmac

Yes, I wrote the articles, and sadly, the spelling and grammar errors contained there in.
As for wiffle, leave him out of it, he's got a day at the beach to plan.