Did you modify the valves in the magazine at all? I have seen youtube video of enlarging the holes.
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Tuning Crosman DPMS SBR build
- Thread starter Hatsan123
- Start date
I’m just trying to defeat the Learning curve on this weapon as I’ve only had this particular Crossman model a short time ..so far Nitrogen works very well ..I don’t think I’ve got a constant 1k fps ..yet .. Sounds like you ve conquered the mods really well .. did you replace the seals with delrins ?
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Guys I tell you I can't rember the person on here that helped me on this crossman dpms build but with the trigger mods and I took all the paint off polished everything on it and machined some pto parts for tolerance specs had a old pink daisy lever action bb gun laying around and used 8 inches of the barrel it will unload a 25 round clip by the time the trigger gets to stopping point I am going to go to work on engineering a new clip if possible but I am pretty sure I can I will keep yall updated and thank you to aeveryone's input on there builds going to buy more for future Frankensteins
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I am New to this bought a dp,s for my son but he nolonger has a desire for it wants to do airsoft. I want to build it to shoot over 1500 fps. I've been playing with the idea of remastering the clip to a straight mag that holds 2 90 gram co2 tanks. And 100 rounds. Any ideas as if this will work and what would I have to do to achieve this?
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The parts in it are not 1500 psi ready you will have to move up to some airplane grade material.they use pot cast metal it might hold together for a little but I d say the bolt would break pretty quick and the trigger mechanism would probaly shoot in bursts instead of fully auto I re machined every part in the trigger and put a stronger trigger spring and I can't stress this enough you have got to tear it down and polish all the parts in it that's a huge help they use some kind of paint to much friction now there might be some people here that have done it but I didn't do it stock but this one I have is at 1700 psi do you have access to a bridge port if so that's the trick if not holler back at me I can help you out
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I'm very interested in trying this out. I found a 15oo psi HPA tank that is close to the dimensions of a 60 round real clip that I am going to use I'm going to build it to fit and look like a "real" AR. I don't have access to a machine I was planning on ordering custom made parts for this build have u considered how much you would be willing to produce a trigger kit polished and everything if so calculate the cost of parts and labor I would be more than willing to pay for it. Like I said I am Very green in this as I just got into it any and all help is welcome.thank you for the help uve already supplied.
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How much do you have in to the project? I just bought one myselfView attachment 124764
Just wanted to reach out to everyone and let you know I just finished doing a build on a Crosman DPMS SBR. I wanted to post this because I have not found any other info on this gun anywhere online. This also motived me to do this build. I did a sevral mods on it, including -
- Two stage hammer spring system
- Conversion to HPA regulated at 1100 psi
- REAL silencer made from mock suppressor
- Polished hammer bolt
- Rubber upper and lower support bushings
- Red dot sight
- Real iron alternate sights with quick use
- Many other cosmetic items
[/LIST=1]
If any body has any questions on this gun I know it inside and out. I would be happy to help anyone else who might be doing mods on this gun. I ran it over a chrony and I am just about at 1000fps. It hits pretty damn hard in full auto. Now if I could just figure out how to build a 100 round clip.
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Actually I just put a ton more into it. It now has:
Even heavier hammer spring system.
Completely rebuilt breach and inner and outer barrel with a 20 3/8 in inner barrel.
4500 psi tank with picatinny mount
Adjustable regulator to shoot from 1000psi ( with factory hammer spring ) for plinking or up to 3k psi per shot. But I find they shoot best at about 2500psi
And honestly alot more that I really don't feel like typing.
I also built my wife a an A4P which is really the exact same gun but with a different stock setup. Both can move steel 5.1 g bbs at 1650 fps and I can push 10g nickle platted lead shot at close to that which is about 60ft lbs of energy per shot. I got a bb through a steel frying pan so thats pretty good.
All semi auto and full auto still works correctly. I have put about 500 rounds through them both and everything is holding together well.
If anyone is interested in this I was thinking of putting a kit together to convert a stock one to a PCP air gun. Please direct message me for pricing and other details.
Thanks!
Super interested man, that looks so sweet!View attachment 124764
Just wanted to reach out to everyone and let you know I just finished doing a build on a Crosman DPMS SBR. I wanted to post this because I have not found any other info on this gun anywhere online. This also motived me to do this build. I did a sevral mods on it, including -
- Two stage hammer spring system
- Conversion to HPA regulated at 1100 psi
- REAL silencer made from mock suppressor
- Polished hammer bolt
- Rubber upper and lower support bushings
- Red dot sight
- Real iron alternate sights with quick use
- Many other cosmetic items
[/LIST=1]
If any body has any questions on this gun I know it inside and out. I would be happy to help anyone else who might be doing mods on this gun. I ran it over a chrony and I am just about at 1000fps. It hits pretty damn hard in full auto. Now if I could just figure out how to build a 100 round clip.
I've just bought miy R1 it's on the way, I know they are essentially the same gun. I am ready to mod the hell out of it, I want to start with a longer barrel, what would you suggest?Upvote 0
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Wow guys, I am in awe. You all have done so much with so little. I just started modding my DPMS with buffer washer mod, 3.97mm magazine valve and waiting for my 1077 barrel that should be here this week. I Have looked into HPA and the magazine fitting would be nice on the side but placement doesn't bother me as much as where to put the bottle. I'm thinking on the buttstock covered with wrap. anyone regrets placing one there? do you like it?
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That is a sweet build, did the Polish on the hammer give you most of your power upgrade?View attachment 124764
Just wanted to reach out to everyone and let you know I just finished doing a build on a Crosman DPMS SBR. I wanted to post this because I have not found any other info on this gun anywhere online. This also motived me to do this build. I did a sevral mods on it, including -
- Two stage hammer spring system
- Conversion to HPA regulated at 1100 psi
- REAL silencer made from mock suppressor
- Polished hammer bolt
- Rubber upper and lower support bushings
- Red dot sight
- Real iron alternate sights with quick use
- Many other cosmetic items
[/LIST=1]
If any body has any questions on this gun I know it inside and out. I would be happy to help anyone else who might be doing mods on this gun. I ran it over a chrony and I am just about at 1000fps. It hits pretty damn hard in full auto. Now if I could just figure out how to build a 100 round clip.
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Doom, you mentioned a breach mod. What did you do? I installed a 1077 barre full length and pushed it through the stock gromet yet it seams im losing air at the breach. If I push the barrel up to the mag it fails to push the BB through, weird. Maybe the barrel is not aligned properly? I'm on 1100ish psi HPA
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Hey fam I'm new to this and wanting to mod my air rife as well. Tons of information on this post I don't even know where to start lol. But you guys have some clean builds looking forward to more knowledge on these parts and things to beef up my air rifle
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I'm doing pretty good bro.. little progress making sure I order all the right parts and still learning the mechanics. Any suggestions?
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