SR-25 Battle Rifle Project

StevieGriff

I've been teasing the idea of this to myself for months now and I've finaly started looking at parts and prices. Hopefully I'll build up the funds for this in the coming months and have it as a winter project!

This will be loosely heavily based around Chris Costa BR thats he has been pictured using at various Magpul Carbine courses.


The base gun for the project is an A&K SR-25 that was used 4 or 5 times before the piston stripped. After the piston stripped I couldn't find a retailer that had the piston in stock (The SR-25 takes a proprietary piston due to the elongated V2 gearbox it uses) so the sr-25 kinda got forgotten about as I moved onto another AEG.

Stock SR-25:


Project plans so far:
Exterior:
Stock A&K receiver.
G&P SR-25 URX
Madbul "ACE" lipo Stock Tube
Magpul ACS Stock
Magpul ASAP Sling Mount
Magpul MOE Pistol Grip
Replica Micro Aimpoint T-1+ High LaRue Style mount
Element Surefire eM961
Magpul XT Rail Panels + Magpul XTM Panels
Magpul AFG
(All/must of the Magpul stuff will be knock offs from pro-t. Linked to PTS stuff because Pro--t website is down)

Interior/Mechbox/Hop up:
Stock SR-25 Gearbox
G&P SR-25 Piston
Modify 6mm Bushings
Modify Non-Ported Cylinder - Stock cylinder is non-ported and seems to be quality)
Modify Bore Up Cylinder Head
Classic Army Helical SR-25 gears
DeepFire 6.02 Tightbore Barrel
Madbul Ultimate Hop Up Unit + Guarder Clear Bucking + element H nub
Airsoft Systems Smart Control Unit - Will decide on this once I see a decent review
G&P 120 Motor

Would love some feedback and suggestions! Thanks

Witcher

Why don't you just keep the stock RIS and outer barrel?

There's no need to change them but if you wanted a shorter RIS you'd be better off buying a cheaper generic one rather than that DD set, the DD has markings etc. but you're gonna be covering it in rail panels anyway so you won't see them. Same with the outer barrel; personally I'd buy generic rather than Madbull and save money because it's not gonna be cheap for all that gear plus shipping.

Puding

have to agree the daniel defence rail would look wrong, to invest that much money and not have it accurate would not be right ideally you need to track down a urx rail system http://redwolfairsoft.com/redwolf/airsoft/Accessories_RIS_Systems_G_P_XM110_Front_Set_RIS_RAS_for_Marui_M4.htm

you should look into maybe getting the stock outer barrel turned down to the correct length

you should have a read of arnies, a guy over there has been making a custom version as well http://www.arniesairsoft.co.uk/forums/index.php?showtopic=182263&view=findpost&p=2373353



also for the price of all the external parts your looking to buy you can almost pick up the g&p or ares model m110 to use as a base http://redwolfairsoft.com/redwolf/airsoft/AEG_AEP_ARES_ARES_SR25_XM110_Carbine_Black.htm

StevieGriff

Thanks a million Pud, I wasn't even aware there was aftermarket SR-25 URX's made by anyone. And that EMC is almost 100% of the image I had in my head for this rifle.

And to answer you question Blay, I am gunna buy generic knock offs where quality won't be compromised. I've had good experiences with pro--t's Magpul knock offs so I'll probably buy all the Magpul stuff from them. I just linked the high end stuff for reference as its easier to find!

(Also forgot to mention in the OP: This rifle will hopefully be my main AEG for milsim and games abroad which is why the price seems a little bit bonkers :P)

Rooky1

This is my version of a DMR rifle.

Started off as a G&G GR25.
Fitted a crane stock to start with.
Retained the original RIS system.
Replaced the outer barrel with a shorter King Arms one.
Guarder hop rubber and nub.
Madbull tightbore barrel.
Original front and rear foldable sights.
Element Special Force CA556 AR203 Flash Hider (14mm CCW)
Magpul angled foregrip.
G&G rail covers.

Rooky1

A couple more photos.

Puding

(Also forgot to mention in the OP: This rifle will hopefully be my main AEG for milsim and games abroad which is why the price seems a little bit bonkers :P)

if your looking to use it milsim be aware of the complete lake of mid caps for the a&k sr25

if your looking to replicate the costa 7.62 you would need to go the route of the urx rail as its not the Leonidas but a knight armament model it is based off the sr25 enhanced match carbine http://www.knightarmco.com/sr25.html

Rooky1

As Puding has mentioned, midcaps are a pain to get.
I use G&P midcaps in my G&G GR25.
They needed a very small modification (takes about 2 mins per mag), but work perfectly.
I don't know whether they would fit the A&K version!

Puding

Rooky1 wrote: »

As Puding has mentioned, midcaps are a pain to get.
I use G&P midcaps in my G&G GR25.
They needed a very small modification (takes about 2 mins per mag), but work perfectly.
I don't know whether they would fit the A&K version!

tbh i read so much conflicting information about what mags would fit the a&k when i was looking to buy one that i did not want to take the risk so went for the ares m110 in the end

but i did read in a number of places that the g&p will fit, hopefully someone on hear might be able to confirm this

edit : also for a traveling aeg your bet off going simple and for something without to many unique internal parts for easy repair on the go

StevieGriff

Puding wrote: »

if your looking to use it milsim be aware of the complete lake of mid caps for the a&k sr25

if your looking to replicate the costa 7.62 you would need to go the route of the urx rail as its not the Leonidas but a knight armament model it is based off the sr25 enhanced match carbine http://www.knightarmco.com/sr25.html

The G&P mid caps fit and feed perfectly, I was lucky enough to snatch 5 or 6 of them awhile after I bought the SR-25. One of the mags was flawed though, the follower spring was somehow too short as it rested about 1 inch down the follower. Had to place BB's behind the spring at the end of the follower to prop the spring further up the follower and it fed fine after that.

And I was looking at that on KAC's website earlier, I think I'm definetly gunna go down the URX route now..

Puding

you could remove the flashhider and gas block from your list as the urx front end contains both the correct ones if you wanted to save a little money and remain accurate

what is the plan with the internals, what would you like to get out of the upgrades, at the moments seems like a lot of money to spend without focus ( i know that sounds a little negative but im not a fan of upgrades for upgrades sack )

StevieGriff

Puding wrote: »

you could remove the flashhider and gas block from your list as the urx front end contains both the correct ones if you wanted to save a little money and remain accurate

what is the plan with the internals, what would you like to get out of the upgrades, at the moments seems like a lot of money to spend without focus ( i know that sounds a little negative but im not a fan of upgrades for upgrades sack )

Well I obviously want accuracy and range for a start, I rarely use full auto so I want fast trigger response and a faster ROF. The SR-25 was previously running on an SRC 100 motor and that struggled to turn the gearbox over.
Got the chance earlier to open up the gearbox and check everything out, which I should of done before I even made this thread.
Gears: Seem 100% fine, no wear at all and quality seems good apart from the Spur Gear which looks eroded/rusted.





Cylinder: It is non ported and good quality. Absolutly no need for a new one. (Not too sure is a ported or non ported more suited to the barrel size?)

Air Nozzle: Very light and weak material. May buy a replacement. http://www.airsoftparts.ca/store2/index.php?main_page=product_info&products_id=1731

Cylinder Head: Doesn't have an o-ring or a slot for one. Could this be a problem?

DeBurca

The surface rust on the spur gear would not bother me too much but the scoring on the bearing surface would
If you are using Ball bearings its OK but not for Metal bushings



I would suggest fiting a cylinder head with an O-ring fitted and it is possible to get Dual O-ring type cylinder heads

StevieGriff

DeBurca wrote: »

The surface rust on the spur gear would not bother me too much but the scoring on the bearing surface would
If you are using Ball bearings its OK but not for Metal bushings



I would suggest fiting a cylinder head with an O-ring fitted and it is possible to get Dual O-ring type cylinder heads

Well spotted man, I just had another look at the gear and it looks time like the alignment of the shaft is why the gear is scored. The angle that the shaft goes off too doesn't seem too severe in the picture but its off at such an angle that the brass sleve around the shaft of the gear can't come off.

Thanks very much for spotting the scoring DeBurca!

Puding

might be of some interest http://shop.ehobbyasia.com/catalog/product/view/id/16840/category/261 , unfortunately will not fit my ares but will fit the a&k apparently

StevieGriff

Puding wrote: »

might be of some interest http://shop.ehobbyasia.com/catalog/product/view/id/16840/category/261 , unfortunately will not fit my ares but will fit the a&k apparently

I reckon its a sign that I should definitely do this project:P
Hoping to buy the URX in the next few weeks but does anyone know if the installation tool is necessary? Thanks

Puding

i believe it is 100% needed for the g&p version as the lower section does not come off like the vfc version

StevieGriff

Puding wrote: »

i believe it is 100% needed for the g&p version as the lower section does not come off like the vfc version

Cool, thanks Pud!