Slugs behavior, any one have an explanation?

[karl_h]

Its incredibly easy to get lucky and shoot an amazing 5 shot group with ammo that your setup doesn't particularly love. Fluke groups happen and really shouldn't be your basis for potential

Sometimes the fluke groups boggle the mind. I have a PB I won't sell to anyone without disclosing it can't hit the broadside of a barn without handloading non-saami spec rounds due to the chamber cut bad from manufacturer. Needs to be rebarreled. It will not shoot any factory ammo < about 6", with most being far worse than that, at 100 yards, but it has put 3 in a row into less than 1 inch, a total fluke that only happened once. Handloads touching the lands to take out most of the inaccuracy caused by the chamber/bore misalignment, and it shoots most anything into 3/4" or less all day long. The manufacturer claims it is in spec and won't rebarrel, bought new(Browning blr 7mag). Gunsmith measured the runout of the chamber vs the bore and that was sent to browning along with rifle, they say it is fine and in spec. Last new browning I ever bought, used to love brownings decades ago, after their response I would not touch a new one since then.

 

[aroundlocks]

Hi fire 012 weigh every slug for same grain.
Then check for defects on the slug with magnifying glass as this will also give you sporadic groups.
Remove moderator if you have one fitted to eliminate clipping.
If you have single shot loader try the method above and see what you get before using your magazine.
If all is good then try magazine.
Process of elimination?

 

[bigHUN]

30y is just way too close for reading the flaw. Btw, for 30y those supposto work as a single hole.
Several suspects...
- slugs are full length body, a lot of friction there and is it even? Wash and lube...
- slug barrel/liner, what is a choke length?
- did you slug your barrel?
- how is the barrel crown?
- barrel harmonics?
- Dwell time? if you got a lot of air blast coming out of muzzle that can create a whole lot of circus.
And you start from here if you really wanna shoot slugs

 

[Airgun-hobbyist]

If you did not make any scope corrections and were just sitting there shooting, I'd say the barrel got a streak of lead in it that effects it. I see that you polish the bore, and wash and sort your ammo. I do these things also, and I have the best results by loading the ammo lightly lubed wet with silicone. The constantly "wet" bore makes things most consistent and predictable. I find that cleaning a bore after using lubed slugs actually changes my accuracy for the worse too. The lubed bore is self cleaning, less the residual microscopic lead removal in the bore that you will always have.

Another thing that could have effected it if you were just outside sitting at the bench is the sun coming out from behind a cloud and it's radiant heat expanding and contracting the action, barrel, and scope, or the opposite of cooling rapidly.

 

[dens228]

- Dwell time? if you got a lot of air blast coming out of muzzle that can create a whole lot of circus.

When I finally started taking a serious effort to dial in slugs it was the valve adjuster that finished the deal. I could get my slugs to just a bit larger grouping than my pellets. As I slowly turned in the valve adjuster the groups tightened up nicely. It didn't take much to improve a lot.

 

[bigHUN]

Also, read about the posts where people talking slugs speeds....not a high numbers making precise shots.

 

[Fire012]

Hey guys
sorry for being away from the subject the past couple of months! i had a mild strock and some health issues, so i took a break from every thing! all good now thank God!
and went crazy and ordered a mini lathe to do my own barrels after what i found chasing the issue!

my findings were: wiered tight spots in the barrel it self, hammer wieght wasn't good " couldn't open the valve over 136Bar of air pressure" therefore my speed wasn't all that good, some harmonic issues "i'm sure of that! need revisiting" and valve adjuster need to be explored!

So what i did, i almost reuined my barrel by polishing it with lapping compoud for car engines valves! "too aggressive" then rectify "saved" it with Rolite metal polish and JB bore cleaning compound. Added about 9 grams of brass wieght to the hammer, which as of now did really good job on opening the valve past that 136Bar limit! i did a test run "not in depth to be a future project" and it opened it @149 Bars with ease! so i dialed it down to 141Bar shooting ZANs 28grn 0.218 cal between 1007 - 997 fps with SD of 3 fps and spread of 10 fps.! which the tightest SD i had with this gun. also shoots ZANs 25.5grn .218 cal @1037 - 1030 fps. Thus hammer and valve adjusment need revisiting!
Untill i dial in the speeds, then i will go back to find the best slug for accuracy. and maybe some more barrel polishing!?

i will keep you posted!

 

[Fire012]

Hi fire 012 weigh every slug for same grain.
Then check for defects on the slug with magnifying glass as this will also give you sporadic groups.
Remove moderator if you have one fitted to eliminate clipping.
If you have single shot loader try the method above and see what you get before using your magazine.
If all is good then try magazine.
Process of elimination?

i did some sorting at the begining when i bought the gun through out the various brands and sizes. didn't noticed much except ZANs were the best fit and most accurate. so, i ditched the sorting and just went with washing, lubing and cleaning the barrel. having the moderator on, gave the best grouping, so i stuck with that too.
then one day i fed up and broke the whole thing down looking at every single thing in it! found the barrel issue, hammer, magazine and the shroud not alligned with the 700mm barrel.

so went with the easy fix and 3D printed a collar to straighten up the shourd with the barrel. then, enlarged the magazing exit hole and smoothed out the breech for better engagment between the slug and the rifling. had a good preformance out of that "the pictures in the first page" but wasn't enough.

then i went a head with polishing the barrel taking it slow as i go. and lastly the hammer and the valve.
so it still a work in progress!
any how thanks for the input. Cheers

 

[Fire012]

30y is just way too close for reading the flaw. Btw, for 30y those supposto work as a single hole.
Several suspects...
- slugs are full length body, a lot of friction there and is it even? Wash and lube...
- slug barrel/liner, what is a choke length?
- did you slug your barrel?
- how is the barrel crown?
- barrel harmonics?
- Dwell time? if you got a lot of air blast coming out of muzzle that can create a whole lot of circus.
And you start from here if you really wanna shoot slugs

yup! exactly my point! they should land in the same hole at 30Yrds! as advertised, the barrel is chokeless. but when i sluged it, found about those wiered tight spots. for now the majority are gone or at least a .216 slug go threw with no effort and no detection of jamming when pushing .217 & .218 except the very end of the barrel "like the last inch" a bit tight! the crown is perfect with no burrs and even surface. i might push the mob while polishing next time and if i damaged it i can fix it with my new toy comming soon! my new lathe!
lets hope it won't get there tho!

the rifilling seems good now, lightly inprint on the slugs.

 

[Fire012]

If you did not make any scope corrections and were just sitting there shooting, I'd say the barrel got a streak of lead in it that effects it. I see that you polish the bore, and wash and sort your ammo. I do these things also, and I have the best results by loading the ammo lightly lubed wet with silicone. The constantly "wet" bore makes things most consistent and predictable. I find that cleaning a bore after using lubed slugs actually changes my accuracy for the worse too. The lubed bore is self cleaning, less the residual microscopic lead removal in the bore that you will always have.

Another thing that could have effected it if you were just outside sitting at the bench is the sun coming out from behind a cloud and it's radiant heat expanding and contracting the action, barrel, and scope, or the opposite of cooling rapidly.

Nope, disn't mess with the scope at all! holding the same POA and go to town. I'm shooting from my shed down range, so not temperature differance there. At the end of each barrel cleaning i would pull a single patch with WD Silicon lube and lightly lube the slugs after washing.
i do agree with you on lubed barrel is a self cleaning i bearly notice any lead residual after shooting via "bore scope" .. very little traces.

 

[Fire012]

When I finally started taking a serious effort to dial in slugs it was the valve adjuster that finished the deal. I could get my slugs to just a bit larger grouping than my pellets. As I slowly turned in the valve adjuster the groups tightened up nicely. It didn't take much to improve a lot.

does it effect your speeds? i plan to mess with mine at the end if i nothing works!

 

[Fire012]

When I finally started taking a serious effort to dial in slugs it was the valve adjuster that finished the deal. I could get my slugs to just a bit larger grouping than my pellets. As I slowly turned in the valve adjuster the groups tightened up nicely. It didn't take much to improve a lot.

That is the thing that messing with my brain! most people would shoot them @980 - 930 fps with great results! then, #TedsHoldOver came on his YT channel shooting NSAs .2165 @1040 fps on Fx Impact with twist rate 1:14 hitting a fly at 100Yrds! and his slugs BC jumped the double!

 

[dens228]

does it effect your speeds? i plan to mess with mine at the end if i nothing works!

It lowers the speed a bit. A little goes a long way.

 

[Vetmx]

If the last inch is a bit tight then you can’t live in denial that your barrel might have a light choke. No matter what Airmaks claims. I’ve recently been testing two lightly choked barrels and it’s not the end of the world or cause for alarm. They shoot quite well with slugs once you figure some things out. Lastly, don’t worry too much about what other people do or claim. Was Ted shooting a Krait with a CZ? No. So you can eliminate everything he said. Take your time and figure your gun and barrel out.

 

[bigHUN]

Clean and wax the liners/barrels, and slug them. If you still notice some "tight spots" I would do fire-lapping.
I did on two of my liners years ago and now still have two new liners waiting for this treat.

Plus some 280 grit diamond paste and shot 10-20 any slow speed that can still eject the pellet at the muzzle. Clean and polish and measure again.

 

[Fire012]

If the last inch is a bit tight then you can’t live in denial that your barrel might have a light choke. No matter what Airmaks claims. I’ve recently been testing two lightly choked barrels and it’s not the end of the world or cause for alarm. They shoot quite well with slugs once you figure some things out. Lastly, don’t worry too much about what other people do or claim. Was Ted shooting a Krait with a CZ? No. So you can eliminate everything he said. Take your time and figure your gun and barrel out.

i totally agree .. i know for sure it would be a challange and a long way to get every thing dialed in.

i was a bit naive to trust the local seller about HP barrels are not choked! but you know "live and learn!"

and to be fair, the gun have good back bone! thats why i'm still at it to make it better.

 

[Fire012]

Clean and wax the liners/barrels, and slug them. If you still notice some "tight spots" I would do fire-lapping.
I did on two of my liners years ago and now still have two new liners waiting for this treat.

View attachment 444619
Plus some 280 grit diamond paste and shot 10-20 any slow speed that can still eject the pellet at the muzzle. Clean and polish and measure again.

I used this, but it was a bit aggressive and scratched the rifiling more than what i like! and i think the diamond paste would be even more and might dig it self in the barrel and cause me more headache to clean!

 

[Vetmx]

You shouldn’t have to polish a barrel, especially with valve lapping compound to get it to shoot. A barrel that would require vigorous polishing is simply a barrel that should be replaced with a better barrel. A friendly polishing is something to help your cleaning intervals and to hopefully keep the gun consistent longer. It’s not a cure for a gun that doesn’t like slugs. Bottom line is you can’t make your gun shoot slugs well by using magic elixirs. It just takes the right combo. Some guns just won’t do it. But with the right barrel, machining and slug they will. Keep plugging away, it’s part of the learning process.

 

[Fire012]

You shouldn’t have to polish a barrel, especially with valve lapping compound to get it to shoot. A barrel that would require vigorous polishing is simply a barrel that should be replaced with a better barrel. A friendly polishing is something to help your cleaning intervals and to hopefully keep the gun consistent longer. It’s not a cure for a gun that doesn’t like slugs. Bottom line is you can’t make your gun shoot slugs well by using magic elixirs. It just takes the right combo. Some guns just won’t do it. But with the right barrel, machining and slug they will. Keep plugging away, it’s part of the learning process.

I totally agree. but unfortunatly, after wasting about a pound of Rolite metal polishing compound on those wiered spots and couldn't get rid off them i went with that valve lapping paste, and went to town, it would be cheaper to buy a low end rifle and break it down for spare parts, than buying a single barrel "here in my country"!! its crazy expensive!
to put things in prespective, an FX 600mm liner would cost $500 and a 700mm would be $600 if you find one! i bought my AirMaks X-700mm HP for $460 new as the dealer claimed! i think he shoved it up my a$$ .. i don't know!

and that was behind my super spending spree! i bought a lathe and few barrel blanks ranging from 580mm to 800mm and some rifilling buttons to make my own! CUZ it would be way cheaper on the long run. i hope so tho!

on the pellet side, i tried all of what ever my hands can lay on! none shot good on either barrels "500mm nor 700mm" what ever the speed may be from 840 to 1020 fps!! past the 50 yrds!

the only slug that show some promise was ZANs .219 before starting messing with it at all.

and i'm not a bad shot, those should be a one hole at that distance! "24.6y"
just to solidify my claim shot those .223 shells by a semi-auto rifle @50 meter indoor range with a crappy cheap scope1-4x25 with no parallex adjustment, no zoom and no brand!

 

[Vetmx]

I can understand the 13 and 25gr pellets not shooting well. But the 18 grain pellets should have done well. If you tried them in the 850 to 930fps range and they sucked, then you definitely have a gun problem. I had a .25 Krait and it shot several pellets pretty good. But it shot only one pellet great. I would think the 18.1 would have the best chance of being the great pellet. You needing hammer weight is another thing that baffles me. How come nobody else needs it to shoot over 135b? I had no trouble cracking the valve with my Krait at 140b and had plenty of hammer spring left to go. Maybe you just got a bum gun. I know I did. Got rid of it.