250Z 250Z tuning, mainly slugs.

[Pumacarl]

So, after not having a good time I did a bunch of reading then went back to the basics. On the original 250 I dropped the psi down to 2000 and started shooting slowly with the butt stock off. At that low a pressure every weight slug I tried had a speed drop when I tightened up the hammer. It didn't take much of a reg increase to see some positive results with the hammer, I'm at 2100 and about 3/4 turn in on the hammer. It's not only shooting much quieter but the groups are much tighter. Not same hole yet, but less than moa at 50 yards. I think I have had that ah ha moment for real today.

I'll tinker with the pressure and hammer some, as long as I have one of the two on in the wee hours of the morning when I'm half asleep. The yotes were back last night and I'm ready for their tuchuses now. I'd like to thank @Cantona256 @Pumacarl & @Airgunandy89 for their help.

@Cantona256 the plenums should have shipped or are going out tomorrow to us.

Are you now just going for ultimate accuracy, speed be damned? Doing that will make the gun quiet, and the groups could be stellar, but you would have a very loopy trajectory. All to ask, what speed are you getting at 2100psi on the reg? It doesn't really matter what speed you run at, as long as you know what it is, and you have a level on your gun so you don't cant at all. The bigger the trajectory is, the more cant matters, and the range has to be known down to the yard too. Accuracy is king, however you have to get it.

 

[Cantona256]

So, after not having a good time I did a bunch of reading then went back to the basics. On the original 250 I dropped the psi down to 2000 and started shooting slowly with the butt stock off. At that low a pressure every weight slug I tried had a speed drop when I tightened up the hammer. It didn't take much of a reg increase to see some positive results with the hammer, I'm at 2100 and about 3/4 turn in on the hammer. It's not only shooting much quieter but the groups are much tighter. Not same hole yet, but less than moa at 50 yards. I think I have had that ah ha moment for real today.

I'll tinker with the pressure and hammer some, as long as I have one of the two on in the wee hours of the morning when I'm half asleep. The yotes were back last night and I'm ready for their tuchuses now. I'd like to thank @Cantona256 @Pumacarl & @Airgunandy89 for their help.

@Cantona256 the plenums should have shipped or are going out tomorrow to us.

BROOOOO GET THEM DOGS!

 

[Bladefin]

Are you now just going for ultimate accuracy, speed be damned? Doing that will make the gun quiet, and the groups could be stellar, but you would have a very loopy trajectory. All to ask, what speed are you getting at 2100psi on the reg? It doesn't really matter what speed you run at, as long as you know what it is, and you have a level on your gun so you don't cant at all. The bigger the trajectory is, the more cant matters, and the range has to be known down to the yard too. Accuracy is king, however you have to get it.

I've always said that I want the slug to go where I'm aiming. The speed isn't damned but what is it without accuracy? It's sitting right around 900fps & 54fpe. I will try to slowly go faster but I'm pinging golf balls between 30 and 55 yards at will. The Zulus makes the yardage and holdover almost effortless. It's also much quieter.

 

[Cantona256]

I've always said that I want the slug to go where I'm aiming. The speed isn't damned but what is it without accuracy? It's sitting right around 900fps & 54fpe. I will try to slowly go faster but I'm pinging golf balls between 30 and 55 yards at will. The Zulus makes the yardage and holdover almost effortless. It's also much quieter.

Quit messing with it! Put a slug or two into a coyote first and see how they do first. After shooting 120fpe out of the EQ I’m even more convinced that 50-60fpe is all you need to take a coyote out to 100 yards. Power isn’t everything. My barra isn’t actually tuned for power it’s for speed. I wanted it to shoot flat and once I got the 30gr to go fast then it was just playing with the weight of the slug for the extra power…

I have yet to shoot anything with the EQ and not get full pass through… and expansion isn’t the issue cuz the exit holes are gruesome.

It’s enough that as I may have mentioned Im not gonna power tune the barra. I’m gonna go slightly heavier with a 34g or 35gr slug but mostly gonna use the plenum to drop reg pressure and gain shots per fill.

Your focus on accuracy shows real responsibility. Putting that slug right where you want it will get the best results regardless.

Good luck bro I’m rooting for you! I wanna see someone get a coyote with the 250z so bad!

 

[Pumacarl]

I've always said that I want the slug to go where I'm aiming. The speed isn't damned but what is it without accuracy? It's sitting right around 900fps & 54fpe. I will try to slowly go faster but I'm pinging golf balls between 30 and 55 yards at will. The Zulus makes the yardage and holdover almost effortless. It's also much quieter.

That's awesome to be doing that speed and power at that reg setting! I thought you were just lobbing them sub-600fps like the inside barn shooters do. At 2100psi my .22 wouldn't be doing much, I have it set at 2450psi and I'm only getting around 45fpe, but it is fun and accurate enough for me.

 

[Bladefin]

That's awesome to be doing that speed and power at that reg setting! I thought you were just lobbing them sub-600fps like the inside barn shooters do. At 2100psi my .22 wouldn't be doing much, I have it set at 2450psi and I'm only getting around 45fpe, but it is fun and accurate enough for me.

I think the power at that reg is coming from both ports being opened up to 4.5mm. The 2nd, stock, 250Z at 2100 is around 820 to 830. The only time I've seen 600's is when my dumb a$$ double loads.

 

[Pumacarl]

I think the power at that reg is coming from both ports being opened up to 4.5mm. The 2nd, stock, 250Z at 2100 is around 820 to 830. The only time I've seen 600's is when my dumb a$$ double loads.

Yeah, I was over embellishing the fact that I thought that it would be slower. I didn't know/remember that you opened both ports. Since you know what you're doing, and how well it works, you should just go ahead and do the other stock gun the same way.

For all the airguns that are available right now, I still think that these guns are the most fun for the buck for the performance that can be obtained from them. I am getting close to abandoning my search for a top tier gun and just getting another .22 and a .25 Barra, and seeing what I can get out of them. I am going to wait to see what the plenums do for the .22 and how ugly they end up being before committing to that.

 

[Bladefin]

Yeah, I was over embellishing the fact that I thought that it would be slower. I didn't know/remember that you opened both ports. Since you know what you're doing, and how well it works, you should just go ahead and do the other stock gun the same way.

For all the airguns that are available right now, I still think that these guns are the most fun for the buck for the performance that can be obtained from them. I am getting close to abandoning my search for a top tier gun and just getting another .22 and a .25 Barra, and seeing what I can get out of them. I am going to wait to see what the plenums do for the .22 and how ugly they end up being before committing to that.

Once I get the plenum installed and the speed where I want it I may do the other one as well. With the plenum I'm thinking about testing a heavier slug, something in the 34~40 range, to see how it does and the shot count. It might be a good idea to port the other one just from an efficiency standpoint.?.?.

A problem I've been having with squirrels is anything under 50 yards, haven't shot one further yet, is I'm getting full pass through, no matter what speed I've shot. I don't know that I can correct that with the grain I'm shooting. Would detuning the 2nd gun and going with a lighter slug be an option, or switching to a pellet under 30 grain?

 

[Pumacarl]

Once I get the plenum installed and the speed where I want it I may do the other one as well. With the plenum I'm thinking about testing a heavier slug, something in the 34~40 range, to see how it does and the shot count. It might be a good idea to port the other one just from an efficiency standpoint.?.?.

A problem I've been having with squirrels is anything under 50 yards, haven't shot one further yet, is I'm getting full pass through, no matter what speed I've shot. I don't know that I can correct that with the grain I'm shooting. Would detuning the 2nd gun and going with a lighter slug be an option, or switching to a pellet under 30 grain?

The pass through problem and big lead flying everywhere is why I got a .22 and stuck to expanding slugs under 23gr. And I can still hit targets at 200y! Maybe, just get a .22? For efficiency though, I would still port the other one. It seems to perform better and certainly not worse.

Another thing to think about is .177. The 10.03gr JSB KO Mk3's are the perfect sub-75y, squirrel sized and down, non-pass through killing instruments. At 980fps, just WOW! EDIT: I just used this on a small rabbit, that was looking away from me 8y away, to the back of the head and blew the entire top of his head off. Like I said, WOW! I would not take or post pictures of that but unfortunately it does need to be done.

 

[Airgunandy89]

So, after not having a good time I did a bunch of reading then went back to the basics. On the original 250 I dropped the psi down to 2000 and started shooting slowly with the butt stock off. At that low a pressure every weight slug I tried had a speed drop when I tightened up the hammer. It didn't take much of a reg increase to see some positive results with the hammer, I'm at 2100 and about 3/4 turn in on the hammer. It's not only shooting much quieter but the groups are much tighter. Not same hole yet, but less than moa at 50 yards. I think I have had that ah ha moment for real today.

I'll tinker with the pressure and hammer some, as long as I have one of the two on in the wee hours of the morning when I'm half asleep. The yotes were back last night and I'm ready for their tuchuses now. I'd like to thank @Cantona256 @Pumacarl & @Airgunandy89 for their help.

@Cantona256 the plenums should have shipped or are going out tomorrow to us.

All preorder plenums have shipped ! I still have a few extras and many other goodies that are turning this rifle into a powerhouse. Or a mild mannered efficient pellet shooter .

 

[Bladefin]

Ok, it's been a minute on this thread. Here's an update.

Going forward I'll be using the following to identify the different guns:

G1 = 1st gun, original hammer lug design. Both valves ported to 4.5mm.
G2 = 2nd gun, new hammer lug. Currently bone stock other than hammer spring experimenting and a ball point pen spring in the back of the trigger.

I do have the slug power kit, but it's not in either gun right now.

G1, I got the plenum installed over the holiday weekend and it was an immediate improvement in fps. Still at 2100psi but instead of 900~905 I'm getting 945~950. No change in accuracy with less than inch groups at 50yrds. It's doing really well and I haven't shot it a lot in the last week. Got it sitting in the bedroom waiting on the late night yotes. I've heard them a couple times and my neighbor has gotten two in foot traps. I can't see through all the leaves at night in the Zulus though. So, I haven't even sighted one yet. It's coming soon, won't be long now.

G2 has seen the most love the last 7 days or so. I got a pack of springs from Home Depot on Sunday with two that were the same size as stock along with a few other sizes in the pack. I cut two down, one shorter than the other and wow what a difference. I stared with the shortest and saw an instant drop in noise and wasted air. I did some tightening from flush and got a consistent 928 to 934fps at 2500psi. Then I wanted to see what stacking a smaller spring would do last night. It's only compressed when the hammer is near the end of being cocked and then for only about a half inch or less of hammer travel. That took the speeds up to 935 to 942 at a half turn less on the hammer, so I know it's adding speed to the hammer. In both configurations it starts faster the first few shots and evens out around 936-938 for the next 10 or so shots then drops a couple more fps. I shot a 1/2" group at 40yrds and that's the best I've done, out of either gun, in a long time.
Once I'm done making adjustments and get a ragged hole I'll try to do a more detailed write up of the setup. Suffice to say that I'm a lot happier now.

I'm still debating porting G2 and putting the plenum on it. Who am I kidding I'll be doing it soon.
G1 will probably be sold or traded before the end of the year.

 

[Pumacarl]

Ok, it's been a minute on this thread. Here's an update.

Going forward I'll be using the following to identify the different guns:

G1 = 1st gun, original hammer lug design. Both valves ported to 4.5mm.
G2 = 2nd gun, new hammer lug. Currently bone stock other than hammer spring experimenting and a ball point pen spring in the back of the trigger.

I do have the slug power kit, but it's now in either gun right now.

G1, I got the plenum installed over the holiday weekend and it was an immediate improvement in fps. Still at 2100psi but instead of 900~905 I'm getting 945~950. No change in accuracy with less than inch groups at 50yrds. It's doing really well and I haven't shot it a lot in the last week. Got it sitting in the bedroom waiting on the late night yotes. I've heard them a couple times and my neighbor has gotten two in foot traps. I can't see through all the leaves at night in the Zulus though. So, I haven't even sighted one yet. It's coming soon, won't be long now.

G2 has seen the most love the last 7 days or so. I got a pack of springs from Home Depot on Sunday with two that were the same size as stock along with a few other sizes in the pack. I cut two down, one shorter than the other and wow what a difference. I stared with the shortest and saw an instant drop in noise and wasted air. I did some tightening from flush and got a consistent 928 to 934fps at 2500psi. Then I wanted to see what stacking a smaller spring would do last night. It's only compressed when the hammer is near the end of being cocked and then for only about a half inch or less of hammer travel. That took the speeds up to 935 to 942 at a half turn less on the hammer, so I know it's adding speed to the hammer. In both configurations it starts faster the first few shots and evens out around 936-938 for the next 10 or so shots then drops a couple more fps. I shot a 1/2" group at 40yrds and that's the best I've done, out of either gun, in a long time.
Once I'm done making adjustments and get a ragged hole I'll try to do a more detailed write up of the setup. Suffice to say that I'm a lot happier now.

I'm still debating porting G2 and putting the plenum on it. Who am I kidding I'll be doing it soon.
G1 will probably be sold or traded before the end of the year.

I missed something, why get rid of the G1? Did it do something wrong, or not as good? They both seem to be performing.

 

[Cantona256]

Once I get the plenum installed and the speed where I want it I may do the other one as well. With the plenum I'm thinking about testing a heavier slug, something in the 34~40 range, to see how it does and the shot count. It might be a good idea to port the other one just from an efficiency standpoint.?.?.

A problem I've been having with squirrels is anything under 50 yards, haven't shot one further yet, is I'm getting full pass through, no matter what speed I've shot. I don't know that I can correct that with the grain I'm shooting. Would detuning the 2nd gun and going with a lighter slug be an option, or switching to a pellet under 30 grain?

The answer to that is actually to go faster. The Franco slugs give me pass throughs as fast as 920fps depending on the grain and they are quite soft.

At 950fps and above they explode on contact. With the 30gr @970 I’ve shot as close as 30y with no pass throughs.

Also with headshots you’re pretty much always gonna get a pass through.

 

[Bladefin]

I missed something, why get rid of the G1? Did it do something wrong, or not as good? They both seem to be performing.

I've toyed with keeping both and having a different slug weight and tune on each. I guess it's still up in the air.

 

[Northeastbeast]

30gn Zan and 49 zan ELR are insane in the barra. Mine is tricked out with slug power kit and a plenum. It dont take much to make these rifles sing.

 

[Cantona256]

30gn Zan and 49 zan ELR are insane in the barra. Mine is tricked out with slug power kit and a plenum. It dont take much to make these rifles sing.

How fast you shooting the 49gr?

 

[Cantona256]

I got the plenum in mine last night finally and wow!

 

[Airgunandy89]

The plenums have been a pretty good success I’ve played with downsizing them by placing lead sinkers in them to decrease air volume and I think we hit the nail on the head … decreased sized plenums are not the way to go, I would be curious to try some bigger ones but I think the small through hole required in these is the limiting factor at that point .. some people have reported some failures to seal , cured by using quality silicone grease around orings or replacing the orings .Also orings do fail and any airgunner knows it’s only a matter of time before a leak occurs especially if you degas often to lower regulator . I have not experienced any failures myself with 4 rifles ..

I do have a few plenums available and quite a few accessories for the barra . I can be found using Facebook at ARC printshop and design ,or email at crossdude2007@gmail.com .

 

[steirman]

Discussions and reads like this are what makes HAM pretty awesome, a new member comes in, people with experience come to help, on lookers read, and we all learn.

As far as the rabbit hole things go, lets just say men have always had an obsession with moving objects through air! lol Golf, baseball, football, shooting, archery, 120mm APFSDS rounds... lmao

Either way this was a pretty awesome read, @Cantona256 do you find you get better accuracy with the 30gr Francos over his 35gr or vice versa?

Armor Piercing Fin Stabilized Discarding Sabot. I miss that one. The 25mm type of course.

 

[Northeastbeast]

How fast you shooting the 49gr?

They like between 800 and 920