POI shift by breech plug

riffraff

Participant

January 7, 2008 at 1:00 am

quote spinj:

I don’t know, the problem you are experiencing just obviously seems like your barrel screws are binding to the bushings and not really locking the barrel securely. Let alone sounding like the very same problem I had before, it just doesn’t make any sense that your POI is dependent on the breech/bolt lock position – it shouldn’t matter whether the bolt is positioned left or right. When everything is snug and tight, this shouldn’t happen.

Riffraff, try removing the barrel then inspect the screws just to make sure that they are not binding to the bushings. You can tell that they are not when there are no marks left by them on the barrel. If not, perhaps the screws aren’t even coming into contact, thus making the barrel have some up/down and side-to-side play and allowing itself to move and also letting the breech o-ring swing it left or right.

spinj, I have done all that many times. I can guarantee it is not my barrel bushings, of that I am absolutely certain.

Bodhisdad, the only reason I havent done what you ask, is the gun now has a sore peter. 😉

Another reason I dont want to mess with the tophat is the throat of the valve bore is already indented by the setscrews, and that is the way it came from the factory.

spinj

Participant

January 7, 2008 at 12:29 am

I don’t know, the problem you are experiencing just obviously seems like your barrel screws are binding to the bushings and not really locking the barrel securely. Let alone sounding like the very same problem I had before, it just doesn’t make any sense that your POI is dependent on the breech/bolt lock position – it shouldn’t matter whether the bolt is positioned left or right. When everything is snug and tight, this shouldn’t happen.

Riffraff, try removing the barrel then inspect the screws just to make sure that they are not binding to the bushings. You can tell that they are not when there are no marks left by them on the barrel. If not, perhaps the screws aren’t even coming into contact, thus making the barrel have some up/down and side-to-side play and allowing itself to move and also letting the breech o-ring swing it left or right.

bodhisdad

Participant

January 6, 2008 at 10:00 pm

Your using a shim, if you turn in the tophat say.05 or .10 then reduce the size of the shim the same. The tophat travel will still be the same as it is now. You can always reverse the adjustment, but you could then at least see if its a binding issue or not. That would shut me up 😆 .

I see with the tophat out and the shim in you have alot less travel then .093. I’d measure the actual travel, that is the distance from top of shim to bottom of tophat. Turn tophat in and find a shim which gives you the same distance. That way you can lock the brech either left or right and should not have any problems, in therory that is.

Good luck with the stock.

riffraff

Participant

January 6, 2008 at 9:38 pm

LOL Rowdy, I will probably never sell this Condor for the same reasons you described. Ive only had it a few months, and nearly left it laying in the snow a few times, but always sat it carefully back on the table and tinkered with it tryng to figure it out.

I have been seeing the left-right POI shift from day one, using 2 different bottles. It didnt dawn on me till yesterday morning the breech plug just might be having an effect on the barrel. I am sure I could adjust the tophat to eliminate this bind, but I am reluctant because I am very satisfied with the performance I get with the gun as-is. That is as long as I follow a few guidelines handling the gun.

As feared, the target I shot yesterday got obliterated by the rain and snow last night. So I shot another target today with the chrony just to give everybody a better picture of what I am experiencing.

I started shooting with a slightly overfilled bottle, it took a few shots to get up to velocity. I try to start at 2800psi, but this time I went over a bit.

Anyway, if you look at the target below, I started in the middle/left side with kodiaks. Starting velocity was 770, 851 and then 883fps. The 4th shot settled in at 935, which is where this rifle averages with kodiaks using the rubber shim under the tophat. 4th shot hit same spot as the 3rd.

I then started rotating the knob to the right, and shot 3 more shots. You can see how they shot to the right. I then shot 5 JSP Predators to the center target with the bolt rotated right, all 5 shots went right, and slightly opened up.

I then shot 5 more Predators to the target right below, keeping the breech knob centered. Shots right where I want them.

5 shots JSB Exact 15.8gr just to left with bolt centered, again right where I want them.

5 Kodiaks at top target bolt centered, just a tad low but centered. I was going to shoot some at the next target rotated left, but 15Â°F temperature outside changed my mind, LOL.

The target, velocity ranges on target

My breech knob position while shooting (gun is uncocked)

And just for the hell of it, the beginning of my new test stock.

Rowdy

Participant

January 6, 2008 at 12:54 pm

Great Topic,

Steller reading guys… I have been with issues of POI shift myself from day one and have blamed mine on two things I have been watching for quite some time now. Now I said day one, thats a bit of hastyness, since I spent the first year or more fixing all the stuff that broke and/or never worked on mine, then I guess I should say after all this would be the day one :):):)

When I have had the time to shoot enough to string with the chrony and get “RIGHT” and @ 25 yards, I see my POI move from right to left if I remember correct. Its been so long since I shot from my bench with this rifle LOL…

This right to left seemed to be from air pressure loss on mine, at least that was the biggest thing I saw, and the fact I think mine at the time was using way to much air per shot, and that not being from the top hat setting I didn’t think at the time as I had this set at like .055″

Then of coarse the frame flex is another issue I have always figured was an area that in my simple mind you could just bank on with just how little support from the lack of material in and around the bolt slide area.

Heck even knowing this I went further and did the side out option to mine and chewed the groove on the right side and chewed out a new bolt slide and new handle. I hated the handle up top… My OEM bolt slide had the air rupture through the cocking knob(handle) so I was having to make a new bolt slide anyway… There was so many things I had fail on this rifle I can’t even remember them all till I look back at all the PIC’s I made of the stuff I had to make to replace them LOL… I just have to LOL about all this too 🙂

I do figure on getting Big A266 or someone to actually turn me out a real true bolt slide from some material I have been looking at making one from as well as a few other goodies I want for a Condor SS project I may want to try out someday…

Then there is the frame flex issues I want to address with a whole new stock build I want to make. When I think about all this and what I really want from this rifle and all, I actually have thoughts about selling this beast all together LOL… With everything I have made and all the trouble this rifle was at the beginning with all the simple stuff flat out right failing. Hopefully I will never really sale this rifle at the point I am at now with all the stuff I have for it and then all that I went through just to get it to shoot in the beginning LOL…

Now that I have bought new tank valves and the fact I have all three of the different sizes of the brandy new tank valves AF has decided to start selling parts like these, makes this a lot better for the owners like me and what I went through, I may just keep the rifle around longer. There was many times I looked at this Condor and thought why am I going to try and mount a 300 dollar set of flip down removeable military field peep sights on what I felt at the time was a 50 dollar rifle :):):)

Now that I have all the time I do in blacksmithing all the chewed and hammered out parts to get her shooting, the trouble of seeking help from a TOG member with the OEM valve body I did and to have the memember never sending me the valve back, not excluding all the accessories I now have for this rifle, I ask myself how in hell would I ever be able to sell this 2000 dollar Rowdy Customized Condor :):):)

I just have to laugh about all that I have learned and experienced as all this has happened through the time LOL… What I want to know from you guys is how do you justify all the work all this takes, now I know there are not many if any had all the trouble I did. At least on this site anyway, I doubt very seriously I could have been the only person to have had all the simplest of issues fail so miserbly on one single AF rifle either… I just find myself at times thinking now that this rifle shoots as well as it does and looks like this rifle does now, why not just cut my losses and sell her and move on???

knifemaker

Participant

January 6, 2008 at 11:12 am

What you are saying makes sense, but I do think BD is corrct. The bolt handle on my ss isn’t in full contact with the frame at all. At first this bothered me. Being use to the caming effect on rimfires. Now that I read this, I won’t worry about the bolt free floating at all. Thanks, Mike

riffraff

Participant

January 6, 2008 at 7:48 am

Thats just the thing Bodhisdad, shot velocity is very consistent so far. I can start at 2800PSI, shoot 50 shots and still have 1800+ psi left. All 50 shots will range from 945 – 970 fps.

I have seen shot strings from talon valves that seem to be much more stingy with the air, but I cant complain with 50 shots at hunting velocities even if I do have to pump a bit to refill.

ahhh, your subliminaly talking me into it. Mebbe I will test smaller tophat clearances tomorrow, but Im gonna need thinner shims I bet. 😉

bodhisdad

Participant

January 6, 2008 at 7:32 am

Not sure what the tophat setting should be for a condor but it seems your probably binding a bit. Seems like a big gap, could be wasting alot of air. For a talon valve we usually start to fine tune at .071. My stock talon valve was set at .068-.067. I’d do some strings and see what kind of consistency i was getting and think about turning the tophat in some till my numbers tightened up. This would also free up some space so you could lock the brech and not be binding against the tophat and the frame to brech lock out position. Just a thought.

riffraff

Participant

January 6, 2008 at 6:59 am

spinj, my barrel bushing screws are nice and snug. I should take some pictures of the targets I shot today if they survive the snow.

I know about the flexing of the frame problem, and I dont even hold the grips at all when shooting from the bench. I just put my thumb behind the grip, and my index finger over the trigger and squeeeze slowly.

Front of gun is on bipod, the buttpad is held by my left hand below my shoulder.

I see this POI phenomenon more noticably when shooting offhand.

If I rotate the breech plug to my left side, the pellet hits to the left EVERY time. Same if I rotate to the right, pellet hits right.

Shooting from the bench, pellets would shift up to 1/2″ either left or right, never up or down. I put 25 pellets into 3/8″ at 35 yards today when I didnt rotate the breech plug.

spinj

Participant

January 6, 2008 at 6:41 am

Riffraff, the problem you have mentioned above is the same one I had experienced before. The reason mine would shoot depending on where the breech/bolt was positioned (locked left or right) was because the bushing screws were loose. It’s quite simple, really, because the barrel isn’t locked down tightly, the o-ring would therefore grab onto the barrel, thus turning it in the same direction you turn your breech bolt. So, you might want to check to make sure that your barrel is secured tightly by the barrel bushing screws as well as the bushings being secured to the frame tightly as well. Locking the bolt left or right should not determine your POI; regardless of where it is set at, your POI is supposed to remain the same.

Now, below is a copy of my post – an explanation – I made about why I was getting POI shifts. You might want to explore this phenomenon out as well just to make sure that you got all things covered:

All right, after doing some major shooting, it turns out that the clearance of the tophat from the brass base plays no role in POI shift. It actually turns out to be in how the gun is held. With all factors/variables considered, such as velocities at or below 900 FPS, consistency in hold and trigger control, breathing, et cetera, what it came down to was the manner in holding the rifle at a particular spot that kept its point-of-aim at a consistent spot.

My Condor SS – and quite possibly most or even all AF rifles – likes to be held just right under the area about two to three inches in front of the trigger guard; my forend hand situated just in between the forestock and the trigger guard is where it’s at for my gun, at least in terms of holding the gun with my forestock-grasping hand. This, along with a light hold on the pistol grip, gives me one-holers even with Crosman Pointed pellets at 18 yards. And the same goes for Kodiaks too. Additionally, I’ve noticed that as long as velocities don’t rise to over 920 FPS, the point-of-impact will remain consistent and dead-on. The reason being so is, well, still under investigation, though I’m preliminarily suspecting and blaming frame-flex. Right now, however, I’m happy that my rifle is dialed in.

For Condor and Talon SS owners, I would advise that you try holding your rifle this way if you are having trouble getting your gun’s POI dead-on stable, of course, granted you took care of the other variables.

Shoot safe, everyone!

All Replies

4 Comments