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Thread: Umarex RP5 pre-review

  1. #31
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    Yeuch

  2. #32
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    A couple of people with the carbine version were at my club the other day and let me have a go. It was fun to shoot, felt powerful enough and I like the look. One of them was having trouble with the pump action being stiff and getting jammed pellets, not sure if this was typical or just because it was brand new and needed wearing in or that it was cold. If I didn't already have a Crosman custom 2400KT incoming I'd look at one of these.

  3. #33
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    Quote Originally Posted by gingernut View Post
    The Carbine looks good and does 10 ft lbs but no open sights.
    It cannot be used as a pistol.

    Good and unusual effort from Umarex.
    Just been watching the airgungear show review and Giles is saying the carbine version is struggling to get over 4 ftlb..
    Was gonna get one for close range barn work but wont bother if its really that low powered!!
    Anyone else chrono’ed one??

  4. #34
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    Quote Originally Posted by Rob-Ontarget View Post
    Just been watching the airgungear show review and Giles is saying the carbine version is struggling to get over 4 ftlb..
    Was gonna get one for close range barn work but wont bother if its really that low powered!!
    Anyone else chrono’ed one??
    Haven't got mine yet (due in Wednesday) but a guy on another site is getting 8ft/lb without a mod on the gun (it seems to be clipping the pellets with his mod on, but whether that is down to the mod or not remains to be seen).

  5. #35
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    Ok, have done some testing this morning using my trusty Combro. For consistency I used RWS Hobby, 11.9gr. I did three sessions, first with a Webley QGS silencer fitted, second with a Swift Stumpy silencer and then with no silencer at all. Temperature indoors a pleasant 18 degrees.

    With each of the silencers fitted I was getting a (disappointing) average of 5.5 ft/lb. Moving to chrono with no silencer, I used the standard practice of inserting a small square of paper between the muzzle and the Combro, which negates false readings from gas on CO2 guns. Oh my...output up to 8.5 ft/lb!

    Just been chatting with my mate about this, and we reckon the RP5 system with choke does not like silencers, possibly due to the physics of what happens when the pellet emerges from the choke. I couldn’t see any clipping on the silencers and testing two seems to rule out a silencer problem.

    I’d be very interested to see test results from Umarex with a silencer/moderator fitted!

    So, in summary, the RP5 Carbine meets or exceeds its stated output...as long as you have not fitted a moderator!
    Any views welcome!

  6. #36
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    Quote Originally Posted by short-carabine View Post
    Ok, have done some testing this morning using my trusty Combro. For consistency I used RWS Hobby, 11.9gr. I did three sessions, first with a Webley QGS silencer fitted, second with a Swift Stumpy silencer and then with no silencer at all. Temperature indoors a pleasant 18 degrees.

    With each of the silencers fitted I was getting a (disappointing) average of 5.5 ft/lb. Moving to chrono with no silencer, I used the standard practice of inserting a small square of paper between the muzzle and the Combro, which negates false readings from gas on CO2 guns. Oh my...output up to 8.5 ft/lb!

    Just been chatting with my mate about this, and we reckon the RP5 system with choke does not like silencers, possibly due to the physics of what happens when the pellet emerges from the choke. I couldn’t see any clipping on the silencers and testing two seems to rule out a silencer problem.

    I’d be very interested to see test results from Umarex with a silencer/moderator fitted!

    So, in summary, the RP5 Carbine meets or exceeds its stated output...as long as you have not fitted a moderator!
    Any views welcome!
    Interesting findings and thanks for taking the time testing 👍🏻

    Have you tried other brands of pellets without the silencer fitted?

    Curious to know if say a bigger sized 5.52 Pellet fairs with the choke etc

  7. #37
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    Good to know.

    But most shooters would want to use a silencer on the carbine?

    I need to do a chrono test on my pistol with and without silencer.

  8. #38
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    Quote Originally Posted by oldskoolzzz View Post
    Interesting findings and thanks for taking the time testing 👍🏻

    Have you tried other brands of pellets without the silencer fitted?

    Curious to know if say a bigger sized 5.52 Pellet fairs with the choke etc
    Cheers. This was a baseline test with a known quantity. I plan to try Superdomes, Accupell and maybe some Crosman HP without a mod fitted to get some comparison.

  9. #39
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    Quote Originally Posted by gingernut View Post
    Good to know.

    But most shooters would want to use a silencer on the carbine?

    I need to do a chrono test on my pistol with and without silencer.
    This is an issue I want to use a silencer but it is clear the RP5 doesn’t like them. Some chrono figures with and without would be good. Is the pistol rifled or choked? The choke appears to be the issue.

  10. #40
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    Quote Originally Posted by short-carabine View Post
    Cheers. This was a baseline test with a known quantity. I plan to try Superdomes, Accupell and maybe some Crosman HP without a mod fitted to get some comparison.
    Ok cool 👍🏻 Keep us updated.

    Quote Originally Posted by short-carabine View Post
    This is an issue I want to use a silencer but it is clear the RP5 doesn’t like them. Some chrono figures with and without would be good. Is the pistol rifled or choked? The choke appears to be the issue.
    Does seem a strange one how a silencer is not only reducing muzzle report but also seriously reducing the power 🤔

  11. #41
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    Quote Originally Posted by oldskoolzzz View Post
    Ok cool 👍🏻 Keep us updated.



    Does seem a strange one how a silencer is not only reducing muzzle report but also seriously reducing the power 🤔
    The choke slows the pellet momentarily and then instead of exiting free, it pushes pressure into a restricted vessel. Physics is not my strong point but I think I sort of understand why this is happening. I plan to try it out with a muzzle brake to see what sort of effect that has.

  12. #42
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    Pistol has the same TG choked barrel.

    I see JSR do a single shot tray as well as the 5 shot mags.

  13. #43
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    Quote Originally Posted by gingernut View Post
    Pistol has the same TG choked barrel.

    I see JSR do a single shot tray as well as the 5 shot mags.
    Ah, then possibly the same effect will apply with mod/non mod setup

  14. #44
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    Quote Originally Posted by short-carabine View Post
    The choke slows the pellet momentarily and then instead of exiting free, it pushes pressure into a restricted vessel. Physics is not my strong point but I think I sort of understand why this is happening. I plan to try it out with a muzzle brake to see what sort of effect that has.
    I get the theory but slightly confused with how the silencer would cause ‘more’ choke effect to slow the Pellet down further

    I would have thought soon as the Pellet exits the barrel regardless of silencer fitted or not it’s at x power as it leaves with the blast behind the Pellet being muted by the silencer.

    Physics isn’t my strong point either but it’s certainly interesting.

  15. #45
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    Quote Originally Posted by oldskoolzzz View Post
    I get the theory but slightly confused with how the silencer would cause ‘more’ choke effect to slow the Pellet down further

    I would have thought soon as the Pellet exits the barrel regardless of silencer fitted or not it’s at x power as it leaves with the blast behind the Pellet being muted by the silencer.

    Physics isn’t my strong point either but it’s certainly interesting.
    Confusing, isn’t it?
    All I know is that you lose about 3 ft/lb when you put a mod on. Never experienced this on any other gun, so am guessing this is down to the choke

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