All this talk about arrowgunz (From the archives) (3) Jan 16, 2020 2:55:46 GMT
Post by bio on Jan 16, 2020 2:55:46 GMT
To make a long story short I only need an 8 mm x .75 die for to thread the 5/16ths aluminum tubing to the adapter so I can test multiple tube inside diameters and lengths for performance and some tips for the arrows to be shooting. If it's not shooting strong enough I have a .25 DAQ Outlaw that might have the same threads on the barrel but charges to 3K psi instead of 2.
Called the tool company that always has everything and they told me they had one of the elusive 8mm .75 dies. Good I thought something I won't have to wait for. So I drove the 12 miles to get it only to find they had a tap waiting for me not the die I asked for. So I bought the tap anyway and went down the street another mile to a hardware store that has lots of inventory and asked for the die. Sure enough they had it so I still got what I went out for anyway. Threaded the 24 inch aluminum tube and snugged it up in the adapter. Then cut and threaded another tube at 18 inches and an arrow as well. All I need is a few practice tips to begin tuning/shooting. But promised the neighbors I would be home to collect a package for them and have a crossbow scope and some AR parts coming myself, Merry Christmas to me, so here I am stuck at home drinking eggnog and eating pumpkin pie waiting for my favorite UPS lady to show up. Such a rough life in the first world it is.
This is my first time delving into the archery and arrow arena so I spent a bit of time researching on the net and so when I found the Easton 2317 would fit on a 5/16ths tube I was done with the research thing. Cheap arrows and they are not as strong in comparison to a few others but the right ID so I bought some to try out. Thought the 5/16ths SS tube would add a bit of strength to the barrel but quickly learned the heavier walled SS tubes were probly not good to hang out so far from the front of breech as there is not allot of strength there and they drooped down under their own weight. So, I went back to the aluminum tube. I am expecting this will werq out eventually anyway and I should learn a bit more as well. I have a bit more experience with low pressure high volume valves than with the higher pressure stuff so the jury is still out on what pressure will werq best for what ID and length of tube. Definitely a lot of volume to fill up with gas though and dwell time will be crucial for best performance for sure. Probly lots of math stuff to help me out here but the brain does not werq well with that kind of thing these days so trial and error it is.
I still have the valve and t-port detuned for shot count and consistency with the 9mm pistol it used to be. Arrows not de-burred after cutting the barrel is not polished up yet either. I just hot glued the tip inserts in the arrows and went to the nearest place that had tips. They only had the 125 gr units that would fit the 23/64ths shaft size of the arrows I have so that's another thing I need to replace when I find what I want. Stuffed some very heavy cardboard boxes with more cardboard and a piece of carpeting cuz it was nasty out and I did not want to go to the range.
24" barrel and arrow just over 100fps
18" barrel and arrow just over 120fps
Then I remembered to turn in the adjuster screw ;^)
Don't think it's any use to test the other tubes until I can flow a bit more gas.
Oh, and I tested with a 1700-1800psi fill as that is the sweet spot with the valve.
I have a long way to go to make it to the 180-200fps I will accept as useful.
Pretty heavy arrow 364gr about .8oz I already ordered some lighter tips and if I cut the length down to 12 inches I could drop a bit of the weight. No tuning done yet but it proves that the barrel and arrow diameters are matched fairly well which is what the first test was all about. Teflon tape is an easy thing to use for a seal so I will do that next and if that helps enough I will install a couple of split and glued Delrin rings or 90duro o-rings before I move on to the t-port then valve. Talk about inefficient less than 18fpe from the normally 40 fpe gun.
New Teflon tape barrel seal installed took it up to 165fps. But the Tefon tape doesn't last more than a couple of shots before it sprays out in tiny flakes all over and makes a big mess. Bigger T-port is on the list. Lighter tips for the arrows are in the mail.
Santa drove a white and blue USPS truck and looked allot like the mail man as he ran from the door after ringing the bell. He left me a nice 2x7 Redfield crossbow scope, 12 more 2317 Easton arrows, 12 new 85gr target tips as well as two 2K output regulators I can use on some new smallish tanks that have been sitting around for years.
I found a heavier but shorter hammer spring and replaced the 125gr arrow tips with the 85gr I just got. After that I put more threads on the barrel so I could screw it further into the adapter so there would be less dead space in the breech t-port area. It shoots 4 shots low of 125 high of 188fps. I have not opened up the t-port as yet. I did almost ruin my breech by drilling the front mounting screw hole out to the size of the t-port port though. Not sure what I was thinking but wish it had not crossed my mind. Since I have brain damage I will blame it on that. I will have to countersink the hole and use a #8 screw to mount the breech at some later date as the #6 almost falls through now.
Put the 16 inch 9mm barrel back on and fired a few rounds over the chrony. I found it shooting 604, 595, 552fps did not waste another pellet as I only have couple of tins left. The 604fps put me just over my goal of 600fps with the valve build. :^) But I still need a bit more for the arrowgun.
I have the scope for when I needs it as it goes down to 2 power it should be OK and was too good of a deal to pass up. Can't see close up anymore without glasses can't see far away with them on, great to get old it is, ;^) so scopes werq well as I can adjust them for my eyes. The valve is not maxed out as yet so until it is I will keep werqing on it. But probly will need to go with one of the Cothran valves eventually as my arms are really screwed up and I am having trouble just pulling the bolt back with the spring I have in the gun now. Wyo has a Cothran and says they pop open with a very light spring.
It took the usual three tries but I managed to make a tubular Teflon seal out of a piece of round stock I ordered. Turned the barrel down a bit and stretched the seal over the end of the barrel and into the groove where it stayed this time. The seal took the velocity up a little. The barrel OD is now .002 smaller than the arrow ID so close enough for me. At least I am over my self-imposed lower limit of 200fps so I can take it to the range and have some fun. Yes, I know I shot my chrony actually shot it three times, I really didn't like what it was telling me, but it lives on so I am not yet a chrony killer.
It was more than difficult to pull the arrows out of my home made arrow stop box with many layers of cardboard and some carpeting inside. So I dreaded testing the gun. Found a Hurricane arrow bag at the local Bi-mart store begging to go home with me so I gave in and brought it with me. What a difference it makes now I can pull the arrows out with one hand even later when they went all the way through. Progressing slowly on the gun and learning a bit as I go. I tried a couple more barrel tubes one with a smaller ID .154 and one with a larger ID .230 as well as one shorter 16 inches and one longer 24 inches. The tube with the smaller ID .154 looked promising velocity wise but only matched the .172 ID barrel I am using at this time in fps. I tried a couple different fill pressures from 2000psi down to 1200psi. Velocity did not vary much with the different pressures which surprised me a bit but it shoots more consistent at the lower pressures.
I ended up cutting the arrows and barrel down to 16 inches so arrow weight is now 332gr. Then put a few more threads on the barrel so there is very little dead space in the breech area now. End result was another 25fps or so. I am slowly getting there.
I put a nice Delrin seal on the end of the barrel and got a bit more velocity but I need the ports to be larger and this valve won't go there due to the excessive angle of the port my bad.
Well since I finally broke down and ordered the Cothran valve I decided to Drill the T-port to .25 inch. Had to modify an 8/40 screw and the tube had to be drilled and tapped to match to fix the mistake I made enlarging the mounting hole in the breech earlier. WOW that .25 port definitely looks way big! The Cothran valve showed up with a port to match so I put it in at the same time.
Those mods let the thing breathe and I got a big jump like 100fps in velocity.
Did a Robin Hood with a couple arrows, while chrony testing, and ruined them both still had not zeroed the scope ouch :^(
Crosman is coming out with a 450+ fps arrow gun soon so guess I need more POWER? So with a bit of polishing, tuning and and a couple hundred more psi now at 2200-2400psi I pumped up the power nicely.
Took the arrow gun to the range a couple days back it's only getting two full power shots at about 150fpe and a third at over 100fpe per fill with the shortened pistol sized Discovery tube so lots of fills. Installed the 9mm barrel and found with pellets in the gun it was putting out just over 100fpe. Had a friend along the day before and asked him to watch one of the arrows I shot that day. Friend is an archer and freaked when he saw or actually did not see the arrow because it was so fast. ;^) It took us fifteen minutes to find the broken arrow, another fifty yards past the 50 yard target, as all he saw was a small puff of dust behind the target when the arrow passed through the target and hit a rock and broke the front two inches off. Next day I went out alone and shot my personal target that usually stops the arrows before the fletching but one managed to make it nearly all the way through at 40 yards so messed up another arrow. I shot for several hours and managed to get the arrow barrel to shoot within a couple inches of the pellet barrel by bending it a bit near the breech. This thing is a blast to shoot. I have a longer tube for more shots but have not yet installed it. So many things to do!!! So much going on life is crazy now that I am trying to have one again.
Before I got the barrel adjusted just right I hit the target stand with an arrow it passed through the 2x6 and into the support 4x4 holding the stand up! Yes, I destroyed it getting it out. ;^( Destructive arrow killing air gobbling arrow gun.
Well this is about the best I can do on the recovery of the arrow gun posts. There were many posts and even more responses but finding all of them and rescuing them from the archives is nearly impossible as most are missing pictures and some are just gone. Finding and loading new pictures to imgur is extremely time consuming as well. Things are very buggy out there in archive land so this is it for now.
PS I found some links out there so the complete build is available for anyone interested.