Flat hop, hard vs. soft buckings.

Discussion in 'Gun Building, Modifications & Repairs' started by excalibur3100, Mar 15, 2018.

  1. excalibur3100

    excalibur3100 Active Member

    158
    32
    Pittsburg
    This has probably been discussed before, and I know there is a DIY flat-hop article, but I was looking on evike https://www.evike.com/search/?search_in_description=1&sort=3a&keywords=Flat+hop&x=0&y=0 and there were some flat hop options. I have an ASG Aug A1 Proline that I want to flat hop and put a 604mm barrel in. I'm assuming I can do this myself, but on the first option https://www.evike.com/products/47834/ there are options for hard and soft. I'm assuming this has to do with the FPS of the AEG, my Aug is shooting 400fps. What would you recommend for this upgrade?
     
    Hangtight likes this.
  2. imnotcrazy777

    imnotcrazy777 Active Member Supporting Member

    1,087
    17
    So I might be mixing up the logic here, but as far as I was aware, soft buckings are generally preferred for a lower FPS/lower stress setup, while harder ones are put into stronger systems. We'd need either the BB weight you're shooting 400fps at, or your joule reading before really helping out.
     

  3. Hangtight

    Hangtight Well-Known Member

    1,150
    447
    With a 400fps gun go for the hard hop rubber and use 0.28 - 0.3g BBs.
    Even with a full cylinder an AEG doesn't have enough volume for a 600mm barrel. Your accuracy will suffer.
     
  4. excalibur3100

    excalibur3100 Active Member

    158
    32
    Pittsburg
    Ah, 400fps /1.4J with .20g bb's (the gun is stock). Would you say this barrel could work with the flat-hop bucking? Just seeing if there is a way to do it myself without mailing the hop-up out https://www.evike.com/products/61990/ .
     
  5. Splode

    Splode Well-Known Member

    1,106
    514
    Fresno
    I use g&g green bucking in a gun that tends to shoot a tad over 400 and it's been fine. Some people say it wont last as long, but I can't tell and I don't really care since it is so cheap.
    I say just flat hop the bucking and get a good concave nub to go with it.
     
  6. Hangtight

    Hangtight Well-Known Member

    1,150
    447
    The barrel won't be optimum with any hop rubber. With 0.28 g BBs and a full cylinder 400mm is about as long a barrel the air volume in the cylinder can supply. And bore up cylinders make almost no difference to that.
     
  7. Splode

    Splode Well-Known Member

    1,106
    514
    Fresno
    Hey Hangtight, question.
    Would my AUG benefit from a windowless cylinder? It's a 509mm prommy barrel. Only thing is that I'm already pushing the fps limit with my current setup. If anything adds more, I'm going to have to change the m120 spring out for a m110. I don't want to do that because I'm already shooting 24 rps and will be changing out the stock jg motor for a high torque. A weaker spring will push it up even higher and I dont really care about RPS, and when things start going too fast, they break or preengage, etc.
     
    Last edited: Mar 16, 2018
  8. excalibur3100

    excalibur3100 Active Member

    158
    32
    Pittsburg
    I have a 509mm barrel as it's stock. Would you recommend a specific flat hop setup from evike?
     
  9. Splode

    Splode Well-Known Member

    1,106
    514
    Fresno
    Id recommend doing it yourself. Prommetheus purple or g&g green bucking. I prefer a concave nub but some people have good luck with flat nubs or even pink eraser mods.
    I believe maple leaf has some kind of pre flat hopped bucking that is supposed to be decent but I could be wrong.
     
  10. excalibur3100

    excalibur3100 Active Member

    158
    32
    Pittsburg
  11. Hangtight

    Hangtight Well-Known Member

    1,150
    447
    With a M110 spring you're good up to around 30rps. A lighter spring doesn't necessarily increase rate of fire. It'll only do that if the existing motor is struggling. If you're worried about rate of fire with a new motor then make sure it is matched to the gearing and voltage to give the rate of fire you want.
    If the cylinder doesn't have enough volume to accelerate the BB to the end of the barrel then consistency and accuracy suffers. As above, 400mm is about as far as you can go using heavier BBs and a full cylinder. My DMR builds are usually 300mm barrels with 0.36g.
    With a 509mm barrel a full cylinder will be more efficient and your fps will go up.
     
    Noob Tech likes this.
  12. Guges Mk3

    Guges Mk3 Administrator Staff Member Administrator Supporting Member Lifetime Supporter

    8,067
    4,611
    Minneapolis
    ML evolved from the A+ designs. It is Not Pre Flat Hopped. They are Packing with elongated contact patch with a nub that pushes down evenly over the whole patch.

    [​IMG]

    There is one for range and one for accuracy. I personally find that they are not that far apart in performance, unlike the diagram the factory lists. This could be due to many factors like bb type and barrel too.

    For AEG's it is called Monster versus Delta/Diamond. With a similar pattern.

    [​IMG]

    With their elongated curved nubs in solid and hollow:

    [​IMG]
    [​IMG]

    For ease and drop in effectiveness it's hard to beat.
     
  13. Splode

    Splode Well-Known Member

    1,106
    514
    Fresno
    I wonder if solid or hollow concave nub would be better.
     
  14. Guges Mk3

    Guges Mk3 Administrator Staff Member Administrator Supporting Member Lifetime Supporter

    8,067
    4,611
    Minneapolis
    Depends on your application...it is a system and thus you need to test and tune.

    With that get the hollow one and if you need it to be stiffer...you can always fill the hole with silicone.
     
  15. Splode

    Splode Well-Known Member

    1,106
    514
    Fresno
    So currently this is the best packing design in your opinion? I'm doing decent with g&g Green but is I can squeeze out a lil more accuracy I'm down.
     
  16. BOA_SP3CT3R

    BOA_SP3CT3R Moderator Staff Member Moderator Supporting Member

    2,898
    1,707
    Bull Shoals
  17. Splode

    Splode Well-Known Member

    1,106
    514
    Fresno
    Sweet, thanks
     
  18. Guges Mk3

    Guges Mk3 Administrator Staff Member Administrator Supporting Member Lifetime Supporter

    8,067
    4,611
    Minneapolis
    Shoot .28g if you are not already and your accuracy will improve.
     
  19. excalibur3100

    excalibur3100 Active Member

    158
    32
    Pittsburg
    I was wondering whether (as I'm new to flat hop and rhop) on an rhop barrel, if there still needs to be a bucking on the barrel with the flat hop nub pressing down on it, or if the contact patch accomplishes this. I have an ASG stayer AUG A1, and if anyone could PM me with the parts to buy for an RHOP setup, I could just buy them.

    Thanks,
    Ramsey/Shadowbane (from CA.net)
     
  20. Guges Mk3

    Guges Mk3 Administrator Staff Member Administrator Supporting Member Lifetime Supporter

    8,067
    4,611
    Minneapolis
    RHOP are pretty complicated. It's not going to be buy and drop in. Unless you buy a matched set of a RHOP kit that corresponds to a barrel. You will need to trim, fit and test as you go...