recomended DMR inner barrel length?

[Isamu]

Im working on transforming my CQBR into a more DMR-ish role, but as a CQBR user, I dont like my AEGs look like Spears, so I was thinking on putting a "knights like" silencer on the CQBR so I could use a 455mm tight bore, or at least thats my original plan.

 

The question is: Is a 455mm tightbore a good compromise between overall length and range/precision? or using a 510mm(or longer) inner barrel will compensate for the loss of "looks and maneubravility (hope I spelled it right )?

 

Thanks

[KMFDM]

Turning a CQBR into a DMR-rifle sounds pretty.... counter productive to say the least

 

In a DMR you should aim to have an as long (and tight) barrel as possible so I would go with the "or longer" alternative if I were you, provided that you have some sort of mock silencer that's long enough to hide the barrel.

[Isamu]

Yeah, it is, but having other AEGs which can fill the "rifleman" role, I wouldnt like to buy another AEG if I can use one I already have just swapping and adding some bits

 

This is my primary AEG

 

 

So it would need a 455mm TB a 430FPs Spring and a harder bucking to fill the DMR with my cheap BAR10 Sight but adding a barrel extender would be easy too...

 

Does 60mm make so much difference?

[GoLgO 13]

anything over 509mm is just wasting your time and money. The only reason to run a barrel longer than 509mm is if you have a gun that has the cylinder volume to support it, such as the PSG-1. Otherwise you are going to have a drastic reduction in range and accuracy.

[Isamu]

Thanks for the tip Golgo, but, does 54mm makes a real difference between 455mm and 509mm?

[A Tobias]

he is saying that actually buying the longer barrel will result in lower accuracy because of the length

go with the shorter barrel and u will be much happier

and your gun will also be more maneuverable

[RSM]

I would reccomend the 455 based on the following

 

+ Its a similar length to the preferred barrel length of VSR users (430mm, I think the optimum for range, velocity and accuracy according to Greg is 480mm, so you're pretty much in the middle of preffered and ideal lengths)

 

+ The M14 scout models use a 420mm inner barrel and we all know how popular they are.

 

An interesting thing about long barrels though, is that I think as long as your cylinder has sufficient volume and consistent flow combined with a good barrel and good BBs to me there is no logical reason why a longer barrel would be any more inaccurate than a shorter one (within reason and if you have done everything to eliminate barrel wobble/vibration) based on the fact there is a PSG in my group that quite happily reaches out to 60m with only a spring and bushing upgrade.

 

To my mind, you only really need to install long barrels if you are going for a particular look. For sheer practicality you should try and get the shortest, most well made inner barrel you can suited to DMR use that fits whatever gun build you are doing, so if a 455mm barrel is 2-3cm short of a silencer then crack on.

[Isamu]

Thanks RSM for the explication, my reasoning was similar to yours, thinking that almost every sniper or DMR has that barrel length but I wasnt too confident with it

 

I will use the 455mm then, since the CQBR inner barrel is 300mm and the silencer is 160mm long, only need to decide the brand between Systema and Madbull

 

BTW, how do you think is the best way to reduce vibrations in the inner barrel? specially in the part covered with the silencer, which is usually not very tight

 

Thanks

[greg]

Thanks RSM for the explication, my reasoning was similar to yours, thinking that almost every sniper or DMR has that barrel length but I wasnt too confident with it

 

I will use the 455mm then, since the CQBR inner barrel is 300mm and the silencer is 160mm long, only need to decide the brand between Systema and Madbull

 

BTW, how do you think is the best way to reduce vibrations in the inner barrel? specially in the part covered with the silencer, which is usually not very tight

 

Thanks

As Dan says, I've come to the opinion that 480ish is about right for the VSR. Longer will give a little more power, but strangely, accuracy starts to wander.

 

For AEG's, I personally find that a shorter, 363 is about as good as it gets.

 

This would make sense, when you consider the internal volumes of the two different cylinders involved. The VSR, has a huge cylinder volume compared to a full aeg.

 

The thing is, that unlike the VSR, longer barrels on an aeg, don't see any accuracy loss, or increase in fps.

 

So, I think it's more a case of 'over 363' is optimum in an aeg.

 

Having said that, I know that some time ago, it was argued that there was little or no accuracy advantage between a 247 & 363.

 

I don't see it my self, but there you go. 'Sale' was going to do a comparison but I never saw the outcome.

 

Personally I use 363 & up in my 'electro-snipers'. I have a 400fps P90 with a 363, which gives exactly the same accuracy as my 400fps M14, with a 509 barrel.

 

There are a lot of threads out there on aeg accuracy, have a bit of a search to turn up more opinions. Most will agree that barrel length is only part of the path to accuracy. Hop, & fps consistency are also key, as is the appropriate ammo.

 

With regard your barrel stability: I've recently been wrapping 'Dynamat' around my vsr inner barrels, along with lining the stock with the stuff. The results have been nothing short of phenomenal. This week, I took a stock G-spec, chronoing 305fps (.2's), loaded the stock & barrel with Dynamat Extreem. Using Guarder .28 hpms, with the hop 3/4 on, I hit a 6" disk @ 50m, 14 times before missing.

 

Not bad for a 305fps, 303mm long barrel, with no internal modifications. Quiet too.

 

I won't tell you what it did after I dropped in a 430x6.03 & 'upped' it to 500fps. Suffice as to say, the customer was very happy.

 

 

Greg.

[RSM]

In my all my guns I use white medical tape and wrap it in a spiral around the barrel (so its fairly wedged in but still removeable, means there is no wobble when the barrel extends pasts the outer and I would like to think it has some vibration dampening effect), its slightly compressible so can be layered up but doesn't make as much of a mess as electrical tape, on top of that I have Doc making me a outer barrel/RAS tube stabiliser that works in a similar way to the VSR barrel spacers as I currently have a free float barrel.

 

Incidentally, I also use Dynamat under the top receiver rail, inside the magwell, the stock tube mount and around anywhere else in the receiver I can cram it and I will be acquiring some teflon tape to do Greg's VSR spring guide mod to to reduce the 'twang' I can hear from the spring. I am so very tempted to put some Dynamat on the outside of the gun then sniper tape over it for further sound reduction.

[jond36]

anything over 509mm is just wasting your time and money. The only reason to run a barrel longer than 509mm is if you have a gun that has the cylinder volume to support it, such as the PSG-1. Otherwise you are going to have a drastic reduction in range and accuracy.

 

 

I heard the same. M16 = 509mm. Make it 6.03 509mm prometheus.

[Isamu]

Thanks men, you snipers never cease to amaze me but that Dynamat thing left me speechles, so this topic will go to "favourites"

 

Just a question, being on a budget, systema or madbull would be my barrel of choice, but I have seen in redwolf the "deepfire 6.02" inner barrel at a very good price, have you got any info on them? I asked google but I couldnt get a clear answer, some people say they are good, other say they are *suitcase... :S

 

Thanks for all the great info

[greg]

Thanks men, you snipers never cease to amaze me but that Dynamat thing left me speechles, so this topic will go to "favourites"

 

Just a question, being on a budget, systema or madbull would be my barrel of choice, but I have seen in redwolf the "deepfire 6.02" inner barrel at a very good price, have you got any info on them? I asked google but I couldnt get a clear answer, some people say they are good, other say they are *suitcase... :S

 

Thanks for all the great info

Yep, Dynamat all the way.

 

I haven'y tried the 6.02's so can't comment.

 

I was always a lalax fan but currently go for Madbull.

 

They are cheaper, lighter & give the same accuracy as the lalax.

 

 

Greg.

[greg]

In my all my guns I use white medical tape and wrap it in a spiral around the barrel (so its fairly wedged in but still removeable, means there is no wobble when the barrel extends pasts the outer and I would like to think it has some vibration dampening effect), its slightly compressible so can be layered up but doesn't make as much of a mess as electrical tape, on top of that I have Doc making me a outer barrel/RAS tube stabiliser that works in a similar way to the VSR barrel spacers as I currently have a free float barrel.

 

Incidentally, I also use Dynamat under the top receiver rail, inside the magwell, the stock tube mount and around anywhere else in the receiver I can cram it and I will be acquiring some teflon tape to do Greg's VSR spring guide mod to to reduce the 'twang' I can hear from the spring. I am so very tempted to put some Dynamat on the outside of the gun then sniper tape over it for further sound reduction.

The dynamat has been good for me.

 

The best I have is a P90, where I really went to Dynamat town, so as to speak.

 

I isolated just about every rattle, twang & bang on that gun. So much so, you can hear the bb's shuffling about in the mag when fired. I wasn't prepared to dynamat the mags. This gun is whisper quiet now. Other than the noise the mag makes.

 

 

Greg.

 

PS, I can't take credit for the teflon taped spring guide mod. This is some one else's baby. I haven't tried it yet.