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ProWin / Dytac CNC Hopup Chamber for M4/M16 Series Airsoft AEG Rifles

50 Customer Reviews

by Dalton B. on 10/29/2023
"I've been using these prowins for a while. I truly believe its the best bang for your buck. Just ordered one, about to order another. My last one came as a Dytac brand, but dramatically increased the straightness and distance of my BB flight path. Paired with an Angel Custom H Nub and Maple Leaf 70 degree bucking. My Arcturus NY02 build now shoots 423 FPS with a .2G BB. Going to order a lower fps spring now! Couldn't recommend enough!
by Kevin S. on 08/20/2021
"Great Hop-Up Unit
Fits into Specna Arms Edge and Arcturus M4s
does not include nub or bucking so keep that in mind
No clicks on hop up wheel but has quite the amount of friction to keep it from undialing itself.
by Bradyn K. on 09/30/2020
"Great unit for a great price. Bought this for my CYMA m4 and paired it with a promy tight bore barrel and a modify hard flat hop up bucking and flat nub. gun shoots way more consistently now. fps is more stable being roughly 393-403. air seal is better and works great with the other stuff i got. adjusting the hopup is also way better than the stock unit, fine adjustments are much easier to do. Great quality product and would definitely recommend, especially if you're on a budget. Also looks are pretty nice, love pulling back the bolt just to see my shiny new unit!
by Gabriel L. on 08/07/2020
"I have used 3 or 4 different hop ups before i tried this one and i can say that this unit is seriously the best. What i mean is that its consistent, it handles high FPS guns well, doesn't fall out of adjustment easily and grabs the magazine every time. For what there asking for it in price is very worth the money. I paired it with a mad bull 6.03 barrel and it makes a 120 dollar gun shoot like a 300 dollar gun. Simple upgrades go far if you put the money were it counts.
by Justin C. on 07/02/2020
"Got this for my Amoeba, fits in perfect with no modifications.

Added with a modify bucking (hard), angel custom 6.01 inner and flat hopped.

Straight laser beams!
by Elton F. on 07/29/2019
"NO FIT ON KWA RM4 and AMOEBA's GEARBOX

But excellent chamber, good quality. A teammate tried it on his Avalon and has very good results.
by Sam B. on 07/10/2019
"Good unit. Does the job very well. Depending on your bucking, it might need some extra material when sliding your barrel and bucking into the unit to prevent rotation.
by Roen Q. on 06/21/2019
"This is hands down the best hop up you can buy. It fit perfect in a G&G Combat machine. It makes an incredible difference. Please buy!!!
by Matt B. on 06/15/2019
"Great hop up unit. The wheel is firm but easy to adjust, the aluminum is very durable, and the blue color looks sick inside my Krytac SPR. Only thing I had to do was space out the hop up unit with O Rings because the set screw is too short to work effectively on a Krytac MK2 SPR. Getting fantastic results with this paired with a Prommy 6.03, G&G green bucking, and R-hop patch by Elvish Tac.
by David B. on 03/19/2017
"I bought this along with the purple promy to flat hop my CM16 Raider. When flat hopping this I would highly recommend using an eraser for the nub rather than wasting $20 on a firefly. Best hop up on the market for this price.
by Thomas C. on 02/04/2017
"I installed this unit onto my G&G CM16 due to intermittent feeding issues and the want to upgrade the hop to a metal unit. I am very well pleased with this hop up and the performance it added to my weapon. Haven't had any feeding issues since the installation 4 months ago. The Hop Up is now installed in a Ares Amoeba and performs just as well. I use a G&G bucking and a 6.03 tight-bore barrel and have good performance. The quality of the product is great and have not run into any fitment issues. I hope that my review is helpful and I would recommend this product.
by Robert G. on 09/03/2016
"I have this on my custom built P☆ HK416 and after a few tweaks. This this in deadly accurate. I play CQB indoors, I definitely think it's worth the investment. I also have other mods as well.
by John C. on 08/13/2016
"Although this unit did not fit in my classic army m4 without trimming the upper reciever and around the spring on the hopup as this is a bit taller than the stock one. I am very impressed with the quality of the unit, and I strongly believe that it helped my accuracy along with the flat hop bucking I purchased. I would recommend this to anyone with the warning that it might not fit properly without some creative installation.
by Nicholas D. on 03/26/2016
"You cant go wrong with the prowin hopup. I have tried a ton of hopups and this by far is the best fitting and most consistent.

My current builds that this hopup is in are an H&K 416 metal receiver, G&P customer built widow maker metal receiver, and king Arms navy seal addition metal receiver.

The one BIG issue I find is that there is a long screw that usually isn't long enough to sit your hopup snug to the gearbox. quick fix is to place your old hopup spring to the end of it and really mash it on there and adjust as necessary to get it snug on the gearbox.
by Aidan S. on 01/26/2016
"I just received this hop up chamber and I installed it today. I currently have it in my 2015 Elite Force m4 cqb. This is a very nice hop up; it is well built, (one piece of solid aluminum) and very effective. I have this hop up in my gun along with a 75 degree Maple Leaf soft bucking and a 6.4 mm Prometheus brass barrel. I have yet to measure the range and accuracy improvements, but I will tell you that it was very significant. This hop up fit well in my elite force m4, but I had to jimmy it around a little. I am not going to give a list of pros and cons, but please be aware of a few things before buying this hop up.

1) the moving parts on this hop up are not assembled; you have to put it together yourself

2) there are no instructions included with the product, but there are many assembly videos on youtube

3) for those of you who are new to airsoft, you will need to buy a bucking and a hop up nub in order to use this hop up

4) finally, there is no spring included with the hop up but they are cheap and not hard to find

In closing, this is a marvelous hop up, especially when paired with a good quality bucking and inner barrel.