These are some very exciting projects, guys! Now that velocity can be increased on many Daisy BB guns, and the pumper smoothbore guns being already capable of high MV, I think improving the accuracy is a very important and much needed step in the evolution of the BB gun!
“hop-up” in BB guns
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I’ve ordered a length of o ring matl. Bought .210” dia. Silicone 70A Should fit with the groove created with 1/4” rat tail file.
Measured the distance rubber extends into the barrel of my co2 bb pistol. It’s about .040”. This gun fires at 300fps. About what I’m getting out of “Cobalts” HP spring in the RR carbine. Should be a good comparison.
Really believe “hopup” is the answer for accuracy and increased bb flight trajectory in these Daisy’s.
Keep “tinkering” and someone will do it. ;>}
Ps. The co2 pistols barrel measures 0.1755” ID. That’s a huge advantage over the daisy barrel——0.1785”.
Measured the distance rubber extends into the barrel of my co2 bb pistol. It’s about .040”. This gun fires at 300fps. About what I’m getting out of “Cobalts” HP spring in the RR carbine. Should be a good comparison.
Really believe “hopup” is the answer for accuracy and increased bb flight trajectory in these Daisy’s.
Keep “tinkering” and someone will do it. ;>}
Ps. The co2 pistols barrel measures 0.1755” ID. That’s a huge advantage over the daisy barrel——0.1785”.
Thx for the inf. I’m working on The Chinese RRider now. Installed one of Cobalts hp springs and waiting for a drilled out air tube (1/8” Id). When I get the velocity up to whatever I get, I’ll install the hopup tubing. But want to establish a benchmark for accuracy without it first. Not only accuracy but flight path/trajectory too.
Could you see a marked difference on the 880 ?
theairgunman
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Yes, the difference is significant, though I'm still hoping for better. Prior to hopup, using the 499 barrel with the 880 gave excellent sub 9 yard groups at 3 pumps. Stretch that out to 20 yards and 10 pumps, and you were lucky to get any BB's on a sheet of printer paper, especially if the bore wasn't spotless.
After fiddling around with hopup, the 880 will put 100% of the shots in a 2.5" group, 92% in a 2" group, and 50% in a 1" group. Quite an improvement, but my personal goal is to get 90+% of my shots in a 1.25" group at that range.
I think hop up can improve our shooting skills. You become very aware of when you are canting your shots as the spin will cause the BB to drift left or right.
After fiddling around with hopup, the 880 will put 100% of the shots in a 2.5" group, 92% in a 2" group, and 50% in a 1" group. Quite an improvement, but my personal goal is to get 90+% of my shots in a 1.25" group at that range.
I think hop up can improve our shooting skills. You become very aware of when you are canting your shots as the spin will cause the BB to drift left or right.
Good input. Didn’t think about looking for the “slice” effect when canting the barrel. Would tell, if in fact the bb is being affected by the device.
The improved grouping tells me, hopup is well worth the “fiddling”.
Thought I’d give an update of what (I think) I’ve learned. I set out to improve the accuracy of a modern (China) Daisy also increase velocity if possible. Accuracy was number one, power is nice but you gotta hit the target first.
As I’ve stated, I’m impressed with performance of the Replica guns available in airsoft and steel bb. A device called “hopup” is used to put backspin on the “bb” allowing the projectile to fly straighter and improve trajectory. So I decided to give it a try.
The ( new) stock guns both the Bucks and the Red Riders were equipped with scopes, shot off a rest with bags at 33 ft. indoors, (two examples of each) and using Daisy’s “match” grade bbs. All these guns typically would put 6 or 7 shots in 1 1/4” with the other 3 or 4 flying out in various directions, creating maybe a 2 1/2” group. All these guns had several hundreds bbs shot thru them over a period of several weeks.
I selected one of the red riders and pulled the barrel. Filed a 1/4” dia. groove about 2 1/2” ahead of the abutment (clear of the air tube when extended). Used a zip tie to seat a piece of silicone oring material in the groove. Exposed just enough of material in the bore to retain a bb when dropped in it. May have .010” of the oring touching the bb ? If I place a rod against the bb, doesn’t take much to push it thru.
With this gun, I’m really shooting some good groups with a rare “flyer”. Routinely Getting 10 in under 1 1/4”, occasionally under 3/4”. Shooting at distance, I don’t see the bbs slicing off left and right as the stock barrels often do.
THis gun chonys at 290 with factory spring. So I thought let’s drop in one on Cobalts “hp” springs with a reamed out air tube 1/8”. Gets 375 fps, but groups go to crap . Shooting 3” and bigger !? Very disappointed. Is the extra shock/vibration the problem. Does the rubber “hopup” need adjustment?
After putting several hundred bbs (cleaning barrel etc). I changed back to factory spring and the sub 1” groups returned. Love to have the 375 fps but——thoughts/suggestions? Thx for listening.
As I’ve stated, I’m impressed with performance of the Replica guns available in airsoft and steel bb. A device called “hopup” is used to put backspin on the “bb” allowing the projectile to fly straighter and improve trajectory. So I decided to give it a try.
The ( new) stock guns both the Bucks and the Red Riders were equipped with scopes, shot off a rest with bags at 33 ft. indoors, (two examples of each) and using Daisy’s “match” grade bbs. All these guns typically would put 6 or 7 shots in 1 1/4” with the other 3 or 4 flying out in various directions, creating maybe a 2 1/2” group. All these guns had several hundreds bbs shot thru them over a period of several weeks.
I selected one of the red riders and pulled the barrel. Filed a 1/4” dia. groove about 2 1/2” ahead of the abutment (clear of the air tube when extended). Used a zip tie to seat a piece of silicone oring material in the groove. Exposed just enough of material in the bore to retain a bb when dropped in it. May have .010” of the oring touching the bb ? If I place a rod against the bb, doesn’t take much to push it thru.
With this gun, I’m really shooting some good groups with a rare “flyer”. Routinely Getting 10 in under 1 1/4”, occasionally under 3/4”. Shooting at distance, I don’t see the bbs slicing off left and right as the stock barrels often do.
THis gun chonys at 290 with factory spring. So I thought let’s drop in one on Cobalts “hp” springs with a reamed out air tube 1/8”. Gets 375 fps, but groups go to crap . Shooting 3” and bigger !? Very disappointed. Is the extra shock/vibration the problem. Does the rubber “hopup” need adjustment?
After putting several hundred bbs (cleaning barrel etc). I changed back to factory spring and the sub 1” groups returned. Love to have the 375 fps but——thoughts/suggestions? Thx for listening.
First, good job on getting your hopup setup shooting well! Sounds like a big improvement from using it.
I was going to suggest cleaning the shot tube of all traces of oil. I use alcohol on a .177 cotton mop but patches work fine if you use a few followed by a couple dry patches to be sure there's nothing left in it. But sounds like you've already cleaned the shot tube.
I would definitely try adding some more resistance from the hopup O-ring.
Also, spring piston airguns, including Daisys it seems, start to become more sensitive to how they're held. Many people have found their groups improve by using what's called the "artillery hold". Airgun writer Tom Gaylord has an article/video on the subject that you may find useful: https://www.pyramydair.com/article/The_artillery_hold_June_2009/63
Good luck and keep us posted!
I was going to suggest cleaning the shot tube of all traces of oil. I use alcohol on a .177 cotton mop but patches work fine if you use a few followed by a couple dry patches to be sure there's nothing left in it. But sounds like you've already cleaned the shot tube.
I would definitely try adding some more resistance from the hopup O-ring.
Also, spring piston airguns, including Daisys it seems, start to become more sensitive to how they're held. Many people have found their groups improve by using what's called the "artillery hold". Airgun writer Tom Gaylord has an article/video on the subject that you may find useful: https://www.pyramydair.com/article/The_artillery_hold_June_2009/63
Good luck and keep us posted!
Yea, oil in the bore is a killer. I’m using Acetone, but wonder about its effect on the silicone O’ring material?
The “spec” sheet says it’s resistant to it. But May change to alcohol.
As for the Artillery hold, I don’t agree with the theory when shooting off a bag. I don’t think the gun knows whether it’s sitting on your hand a bag or a PJ sandwich. I think it was developed to reduce the grip effect when shooting offhand. Which I can understand. These guns “jump” forward when fired and coupled with the low projectile velocity, the projectile is greatly effected by guns movement—-much more than a high velocity round. And So the idea of trying to repeat recoil every time.
I do not grip the forearm when on a bag, the weak hand is kept back under the stock. I place as little as possible pressure with the trigger hand on the grip. True of all rifle bench shooting.
Gaylord says the pellet does not start down the bore until the piston bottoms out ?? Where does all the air go before the pellet moves ?. Don’t understand his thinking here.
My next trial is get someone to hard chrome plate a shot tube. Like to reduce bb to bore clearance by several thousands. I believe this will have a great effect on many of the issues we are working on. Thx for the feedback.
The “spec” sheet says it’s resistant to it. But May change to alcohol.
As for the Artillery hold, I don’t agree with the theory when shooting off a bag. I don’t think the gun knows whether it’s sitting on your hand a bag or a PJ sandwich. I think it was developed to reduce the grip effect when shooting offhand. Which I can understand. These guns “jump” forward when fired and coupled with the low projectile velocity, the projectile is greatly effected by guns movement—-much more than a high velocity round. And So the idea of trying to repeat recoil every time.
I do not grip the forearm when on a bag, the weak hand is kept back under the stock. I place as little as possible pressure with the trigger hand on the grip. True of all rifle bench shooting.
Gaylord says the pellet does not start down the bore until the piston bottoms out ?? Where does all the air go before the pellet moves ?. Don’t understand his thinking here.
My next trial is get someone to hard chrome plate a shot tube. Like to reduce bb to bore clearance by several thousands. I believe this will have a great effect on many of the issues we are working on. Thx for the feedback.
I am really thinking on the magnet idea. Perhaps I could machine a magnet into a barrel so it goes all the way down the top ... It's an idea. Is rare earth (neobinibinidumidumsdfao?) expensive?
As for the projectile not moving until the piston bottoms out, the air is getting compressed, and the re expansion of the air is what pushes the projectile forward.
My idea is to hack together a PCP platform for this reason. Except for my 499b, I don't much like piston guns forward recoil.
As for the projectile not moving until the piston bottoms out, the air is getting compressed, and the re expansion of the air is what pushes the projectile forward.
My idea is to hack together a PCP platform for this reason. Except for my 499b, I don't much like piston guns forward recoil.
Heh ... kinda feeling like I put a damper on some lively discussion. I hope my statements didn't sound "know it all" or anything like that. I have been scouring the internet for the last week or so for information on how to get some spin into a BB. It seems not many have tried the magnet idea. I have a couple of red ryders we haven't shot in a few years because the accuracy is terrible. I may try some magnets on the shot tubes of these. I am really excited about this hop up idea!
I have lofty ideas of adapting a PCP powerplant to something that holds a reservoir or at least can act as something of a repeater, shoots 900fps (ricochet can be dangerous here!) and produces sub 1" groups at 50 yards. Perhaps this is impossible. It doesn't seem like any have tried...
I have lofty ideas of adapting a PCP powerplant to something that holds a reservoir or at least can act as something of a repeater, shoots 900fps (ricochet can be dangerous here!) and produces sub 1" groups at 50 yards. Perhaps this is impossible. It doesn't seem like any have tried...
Nah, you didn't put a damper on it, it ebbs and flows. Will be busy a few days then sit quietly for a few.
I'm interested in seeing what your results are- this is a largely unexplored avenue and there's a chance you could hit on a killer method!
One magnet experiment I've seen positive results from was using a very strong magnet to delay the release of a BB when using the Daisy 499 abutment and shot tube in a custom Daisy 1938B Red Ryder. It's in the thread here: https://www.thehighroad.org/index.p...le-more-power-in-a-15-00-daisy.807316/page-30
I'm interested in seeing what your results are- this is a largely unexplored avenue and there's a chance you could hit on a killer method!
One magnet experiment I've seen positive results from was using a very strong magnet to delay the release of a BB when using the Daisy 499 abutment and shot tube in a custom Daisy 1938B Red Ryder. It's in the thread here: https://www.thehighroad.org/index.p...le-more-power-in-a-15-00-daisy.807316/page-30
rws_53
Member
You don't see many BB guns with hop up.
I have two 4.5 mm (.177) steel BB guns that do.
Sig Sauer P226 X-Five Open with non-adjustable hop up
notice there is no adjustment wheel and linkages included on the steel BB version as found on the Airsoft version
fixed bucking nub protruding into chamber
Umarex Beretta M9A3 with adjustable hop up
shows the adjustment wheel
rubber bucking
shows how the hop up adjustment ring acts on the rubber bucking
bucking nub protruding into chamber
I have two 4.5 mm (.177) steel BB guns that do.
Sig Sauer P226 X-Five Open with non-adjustable hop up
notice there is no adjustment wheel and linkages included on the steel BB version as found on the Airsoft version
fixed bucking nub protruding into chamber
Umarex Beretta M9A3 with adjustable hop up
shows the adjustment wheel
rubber bucking
shows how the hop up adjustment ring acts on the rubber bucking
bucking nub protruding into chamber
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Good info. And pics. My Colt Commander (Steel bb) by KWC ? I think.
Has a nonadjustable “nub” protruding into bore. Bore dia much smaller than the typical Daisy BB gun Which also contributes to the guns excellent accuracy and velocity. The Daisy “match” bbs work well in it. The new “Marksman” bbs are a great improvement in the Daisy guns. Be afraid of them in the Colt, but haven’t actually checked.
Haven’t determined if the silicone “nub” I installed in a 1938B shot tube has altered the guns performance. After several thousand rounds it’s still in place.
I have determined oil or grease in the bore will ruin accuracy in the Daisy.
I degrease bore before any testing.
Has a nonadjustable “nub” protruding into bore. Bore dia much smaller than the typical Daisy BB gun Which also contributes to the guns excellent accuracy and velocity. The Daisy “match” bbs work well in it. The new “Marksman” bbs are a great improvement in the Daisy guns. Be afraid of them in the Colt, but haven’t actually checked.
Haven’t determined if the silicone “nub” I installed in a 1938B shot tube has altered the guns performance. After several thousand rounds it’s still in place.
I have determined oil or grease in the bore will ruin accuracy in the Daisy.
I degrease bore before any testing.
Cvans
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- 463
Dave I have to admire your quest for accuracy. Personally feel if you can't hit what your shooting at velocity means nothing. Sure hope you come up with something that meets your expectations.
After working on and shooting pellet guns since the 60's some thoughts on the firing cycle of spring piston guns have come together. You stated that the gun moves forward at the end of the cycle and I agree but at the beginning of the cycle I believe the gun moves rearward. The ends of the spring when released will try and move in opposite directions. The FWB-300 with it's floating breech moves rearward when the gun is fired thus no felt recoil. Love that gun.
Wish I had an old beater that I could try shooting BB's out of. I also agree that the lock time is a lot longer on these airguns which makes any gun movement more critical.
Thanks for sharing your findings. And thanks to Cobalt for the link to this topic.
After working on and shooting pellet guns since the 60's some thoughts on the firing cycle of spring piston guns have come together. You stated that the gun moves forward at the end of the cycle and I agree but at the beginning of the cycle I believe the gun moves rearward. The ends of the spring when released will try and move in opposite directions. The FWB-300 with it's floating breech moves rearward when the gun is fired thus no felt recoil. Love that gun.
Wish I had an old beater that I could try shooting BB's out of. I also agree that the lock time is a lot longer on these airguns which makes any gun movement more critical. This is something that is beyond my comprehension. Would like to know how he came up with that idea.
Thanks for sharing your findings. And thanks to Cobalt for the link to this topic.
Looking at your pics and Getting ready to “notch” another 1938B shot tube.
Your pic show the “bucking” protruding much further into the tube than my 1st attempt. And material has a “V” notch cut into it, which I won’t attempt.
How would you describe the materials “flex” ? Firm, hard, soft ? I used a silicone tubing softer than most O’rings. Don’t know where I got it, 1/4” dia.
I place the notch just in front of the air tube when extended -2 1/2”. Concerned tube would be damaged and/or tube would accelerate wear of bucking. Is that the correct word ?
Thanks for your info. Dave.
Your pic show the “bucking” protruding much further into the tube than my 1st attempt. And material has a “V” notch cut into it, which I won’t attempt.
How would you describe the materials “flex” ? Firm, hard, soft ? I used a silicone tubing softer than most O’rings. Don’t know where I got it, 1/4” dia.
I place the notch just in front of the air tube when extended -2 1/2”. Concerned tube would be damaged and/or tube would accelerate wear of bucking. Is that the correct word ?
Thanks for your info. Dave.
rws_53
Member
the rubber is very pliable
from muzzle end
this shows the barrel notch cut for the bucking...the red line indicates where the protrusion is that fits into the barrel notch
Uploaded at Snapagogo.com
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Ok thanks. What catchs my eye is the width of the notch. Appears less than 1/8” ? I’m working with 1/4” material. Projectile is going to be exposed to much more surface of material as it passes thru bore.
Will have to locate more tubing if I go with the smaller Dia.
I have several spare shot tubes to play with, probably go with the material I have first.
Thanks for all the info. The Pics are indispensable
Will have to locate more tubing if I go with the smaller Dia.
I have several spare shot tubes to play with, probably go with the material I have first.
Thanks for all the info. The Pics are indispensable
X2- these photos are the only ones I have seen that show the details, thanks rws_53 for taking the time to post them! This thread is outstanding.
rws_53
Member
an easier approach may be to order some bucking...Google "hop up bucking" and purchase the least expensive for your testing purposes
most of the listings are for 6mm airsoft barrels so would prolly be too big to fit over a 4.5mm barrel...but you could cut part of the bucking tube off opposite the nub...place the bucking over your barrel slot and tape it or zip tie it to hold it in place. Using a zip tie you could conceivable vary the pressure on the nub making it somewhat adjustable in the depth it protrudes into the barrel.
cut bucking at blue line equally on both sides...place on top of your slotted barrel...fasten in place
Edit: After reading back through this thread I see theairgunman already mentioned using zip ties
varying tightness with a zip tie at red arrow would allow varying depths of nub into barrel...try different depths and note effect on flight of BB
Uploaded at Snapagogo.com.
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rws_53
Member
I did some testing with the adjustable hop up on my Umarex Beretta M9A3 pistol. Shot groups at 5 yards out to 25 yards. Making adjustments from minimum to maximum hop up did not have any effect on POI with steel 4.5mm BB's. It was suggested to me to try 4.5mm plastic BB's which are much lighter. Unable to find any in the US a guy from England is sending me some next week.
Hmm, maybe spinning wheels—- But I did something last week that encouraged me. Have a pair of 1938Bs, bought at same time, one with my homemade hopup device the other stock. Shooting the new “Marksman” BBs
Both with scopes mounted.
Zeroed both at 30 ft, both shooting under 1” groups, then moved to 90ft. The stock gun grouped 8” low, the modified gun only dropped 4” and grouped slightly better under 3, the other over 4”.
So, I’m going to notch another barrel and add one of Cobalts HP springs.
With the increased velocity, I’ll increase depth of notch and allowing the hopup to hopefully add spin. Time will tell.
Dave I have to admire your quest for accuracy. Personally feel if you can't hit what your shooting at velocity means nothing. Sure hope you come up with something that meets your expectations.
After working on and shooting pellet guns since the 60's some thoughts on the firing cycle of spring piston guns have come together. You stated that the gun moves forward at the end of the cycle and I agree but at the beginning of the cycle I believe the gun moves rearward. The ends of the spring when released will try and move in opposite directions. The FWB-300 with it's floating breech moves rearward when the gun is fired thus no felt recoil. Love that gun.
This is something that is beyond my comprehension. Would like to know how he came up with that idea.
Thanks for sharing your findings. And thanks to Cobalt for the link to this topic.
Thx Cvans, enjoyed uer info. I started with the excellent Benjamin pumper, sixty some yrs ago—-How’d that happen? Enjoyed many since then, while working with kids and now gkids. Had a FWB once, barrel cocker, heavy kicker without the recoil system. Never able to shoot it well, my problem not the gun.
Never thought about the springer kicking back first, but that makes sense. They’ve always been difficult to shoot, so eventually I got into PCPs Solved the recoil issue. Not a cheap solution, but $$$ is not to be an obstacle when guns are involved
.
Cvans
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- Feb 21, 2019
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Dave in a land far away and a long time ago my first was a pumper also. Crosman 140. Shot that gun a lot and still had it when I moved to SD in the 70's.
Looking forward to the results from your next test. Should prove the validity of your experiments. Got my fingers crossed that this works for you.
Looking forward to the results from your next test. Should prove the validity of your experiments. Got my fingers crossed that this works for you.
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