Help me with a DMR role

[freshage]

Hey again guys! I've decided on a semi auto DMR with a FPS of 400-450. Site restriction is 435 at Absolute Airsoft. So yea, I'll aim for 450 as I'm sure with hop up it will bring it down a little.

Anyway, as I understand, almost every AEG can be modded to be a DMR. I have a few questions.

If going down the DMR route, is it better to get a specifically designed DMR (M16) or get a normal AEG (M4) and modify?

Scope, I imagine a 1.5x - 4x scope will be good as anything more is a bit OTT.

What are the normal modifications for DMR's? In laymen's terms. And why are the modifications done?

Thanks!

 

[Colonel Kurtz]

http://www.airsoftsniperforum.com/43-longrange-aegs/892-holy-grail-building-your-dmr-aeg.html

Best introductory guide i found.

But yes you can make any rifle a DMR, only difference is how much you need to replace. You'll want one that can support a long barrel well rather than ending up with a foot long silencer, or can just end up looking silly and easy to snap if dropped.

But it' not an easy task, and one that many just seemingly use as an excuse to buy every aftermarket part they can find for their AEG.

I play at Absolute Airsoft occasionally and pretty much half the guys there have what they claim to be a 'DMR' so guessing you've been chatting with them lol. Out of the ones i looked at I'd only count a couple as anything more than a pimped aeg with harder spring.

 

[freshage]

I've not been to absolute in years. I'll be going to my first game in a few weeks after 12 years! Need to hire first to get licence.

And yea, from research there is a DMR looking gun, or a dedicated proper DMR. I personally don't like the silenced look with a scope big enough to see the flag on the moon. I like a short range small scope with a red dot as it's practical and a clean look.

 

[Lozart]

How about the classic DMR - the M14? Decent length barrel, nice quiet gearbox and you have the option of eith the good old fashioned style M14, the DMR style ones the G&P sell or the various EBR models if you want something with rails.

 

[freshage]

Rails are none essential I think chap, mainly a sight mount is needed.

May I ask, why is there a requirement/need for a quite gearbox? Noise doesn't bother me and I'm sure the idea of stealth is out of the way in most games. Is there another reason for getting rid of noise?

 

[Lozart]

Rails are none essential I think chap, mainly a sight mount is needed.

May I ask, why is there a requirement/need for a quite gearbox? Noise doesn't bother me and I'm sure the idea of stealth is out of the way in most games. Is there another reason for getting rid of noise?

Because it's annoying? Granted it's less of an issue as a DM than as a sniper but it's just something that the M14 generally benefits from. The gearboxes tend to be quiet.

Also you can get a sight mount for an M14 pretty easily. The Socom models have a short rail built into the top cover as do the G&P DMR ones. The EBR models have all the rails you could possibly want!

 

[Airsoft-Ed]

Doing it properly is expensive.

Getting a gearbox to reliably, efficiently and effectively pull a spring capable of producing 450 or so fps is not a simple task.

There's two ways you can do it.

Cheap:
Buy the spring, fit it and suffer with the slow and inconsistent trigger response and rate of fire, as well as all the gearbox jams from the poor gearing.

Ooooorrrrrr

Not cheap:
You can change the gears to a better ratio, to make more efficient use of the motor's power. It's like gears on a bike. Higher ratio makes a less powerful motor capable of pulling a more powerful spring. Or you can go for a lower ratio, which means you'll need a stronger motor, but it'll pull the spring back a lot faster.

You'll need to change the piston to one that can deal with the added stress of an up-powered spring, otherwise the teeth will just strip.

Once you've done that what you have will be a lot more workable and the rest is more about tuning it properly to get it where you want it to be, and that's really what makes it expensive.

For example, you could go with a weaker spring, so the gearbox won't struggle as much, but then make all the air seal related parts super efficient and air tight so you can get more fps from said weaker spring. Just makes the whole thing a lot more efficient.

You'll probably want to fit a mosfet to allow use with higher voltage batteries, to decrease the chance of a gearbox lock up, because you'll have to lock the gun to semi only if you're running it at that sort of power.

You could get a bore up cylinder kit, high grade hop and barrel, new nozzle, cylinder and piston heads, spring guides, bearings/bushings... Pretty much everything can be made better.

You ought to look into the idea of using a Polarstar Fusion Engine instead, because if you want to do it properly with an AEG it'll cost about the same amount of money, but a P* will always do a better job of it, and always be a lot more reliable and consistent, as well as being infinitely more easy to tune.

Plus with a P* you can also change it all back to a regular field rifle on a whim.

 

[GiantKiwi]

....or GBBR. (Surprised Ed didn't jump on this er train... )

NPAS or equiv for fps regulation.

Wider bore barrel (6.08mm or larger) + ER-Hop + EM Nub for consistency at range.

Mechanically locked semi auto is a piece of cake on most systems.

 

[Spatch]

It's worth checking with your local site as to what they class as a DMR, 2 of the 4 sites I play at will only accept a DMR if it is a 'real' DMR, ie M14 etc, it stops people taking a short M4/MP5 locking it to semi, hiking the fps to 425, fitting a mosfet and an 11.1 and spamming the shite out of it

 

[freshage]

The good news is I need to go to site 3 times before I get the licence thing.

So I'll have a good ol' chin wag with the marshals if they are not too full of em self's.

 

[Spatch]

The bad news is you just referred to 'the licence' prepare for the onslaught

 

[Lozart]

*ahem*

It's not a licence.

/discussion

 

[GiantKiwi]

It's worth checking with your local site as to what they class as a DMR, 2 of the 4 sites I play at will only accept a DMR if it is a 'real' DMR, ie M14 etc, it stops people taking a short M4/MP5 locking it to semi, hiking the fps to 425, fitting a mosfet and an 11.1 and spamming the shite out of it

Wish more sites would do this - Worst i've seen is an MP5K being claimed as one. >.>

 

[freshage]

Hahahaha, ok, not licence. The legal rights to buy a replica airsoft rifle/handgun.

And yea, I can imagine a bunch of muppets slapping on a 12x scope onto an M4 with an uprated spring hoping to claim DRM. Having used a 4x a lot, it's a 250yd+ scope. So 2x is the realistic max you need unless it's a good few acres accross.

 

[TacMaster]

When it comes to rifle size AEGs for DMR conversion, there is literally no need to worry about barrel length. The DMR building blokes on Airsoft Sniper Forum generally agree that a DMR can have an inner barrel as short as 363mm (they tend to be the accepted authority on mostly everything DMR/Bolt Action related. This thread may be useful to you).

What makes a good DMR?

• A consistent power output (worst case scenario you should only have up to ±2-3 FPS difference in BB velocity)
• A stable and consistent hop and well made (straight as possible) barrel
• High quality heavy ammunition; 0.3-0.4G BBs are the accepted weight, there's a lot of debate on the best manufacturer though

You will also be looking at £££ to set an AEG based one up properly. As Ed has said, there's also the PolarStar engine option (uses high pressure air or HPA to propel the BB) or gas blowback rifles (GBBRs).

I would not recommend doing a DMR project for your first gun, the same as I would not recommend trying to create a perfect airsoft sniper rifle as an initial gun.

As for sights- I find a red dot is perfectly fine for me. You can get flip-to-side magnifiers as well, and some scopes have screw-in magnifiers available for them.

 

[Mr Monkey Nuts]

From everything you have written you don't need a DMR, you just need a good standard AEG.

I echo lozarts suggestion of an m14! May be a nice compromise.

The advantage of 450fps is eroded by the semi only and low cap mags. Don't underestimate the ability to suppress on full auto, when you lose it, you will miss it.

Dot sights are more than accurate enough for airsoft and scopes can offer a disadvantage is aqua siting times, although a combo of scope and dr sight or relex and magnifier could be an option.

 

[Spatch]

Point of fact, one I've just finished and performing exactly as tac says, I'll just leave this here for you