Inconsistant S410

[jamiedenny]

Hi All,

 

I finally took delivery of my F1 Chrony yesterday. Unfortunately (maybe not) I was struck down with chronostitis and tested everything in my cabinet.

 

My main focus was on my S410 (sub 12ftlb). I have noticed over the last few months the ever proven s410 is proving to be a little "off". After 10ish shots they always seemed to be dropping below zero. As I spend 95% of my time huntnig in the field not target shooting I spent most of the time doubting my ability. After testing my S410 its clear something isn't quite right, my string was as follows:

 

799

798

783

780

745

744

740

740

738

740

etc... I didn't drop below 735

 

From my calcs this puts the rifle starting at 11.9 and sinking down to 10.7

The rifle is .177 and I'm using 8.4 grain Air Arms Field. I didn't weigh the pellets because a.) life it too short and b.) I will never ever weigh them in use. I did however proove my testing by re-filling the tank to 180bar and running the test 5 times with very,very similar results.

 

As I have a pair of hands I stripped the rifle down for a complete clean. As its anti tamper I (hold you horses, read on) I drilled out the necessary to remove the top from the bottom action. I removed everything including the main spring and gave it a good clean and light oil with gun oil. The only section I didn't remove was the air chamber and valve. I replaced the main spring from a known supplier.

 

After putting everything back together. I went back out to test and achieved almost exactly the same results.

 

I'm fully aware 11.99 is too close for comfort and the drop to 10.7 is going to really affect my accuracy. I could remove the top anti tamper and test it further. As far as I know this will only increase the power output not help smooth something like this out.

If it turns out to perform best above 12ft then it can go on ticket. However I think there is more of an issue with the power drop, which will happen regardless of the power output.

 

I've just ordered a set of new seals but wondered if anyone had any other ideas.

 

If your more talented than a man with a pair of hands and access to the internet; and think you can help then PM me.

 

Any other advice is greatly received.

 

Many thanks

Edited May 12, 2012 by jamiedenny

[turbo33]

The s410 is un regulated as standard. The difference in power from 799 to the satblised 735 wouldn't mean much in real terms. For example my rifle (the same) is zero'd at 36 yds. If i put the data you have given into chairgun, the difference at 30 yds is .2 of an inch or around 4.5mm. That corresponds nicely with the so called "sweet spot" which in mine is 165-170 down to 100...proven by 10 pellets through yours and then settling at 735. Which may dissapoint you at 10.7lbs, but that still carries over 4ftlbs of energy at over 70 yds. The research shows 3ft lbs is necceary to take out a bunny with a head shot. At a more realistic distance ie 36 yds there is 6.5ft lbs of energy. More than twice the amount neccesary.

My advice would be to run a test from 170bar till the power falls off and again at 165 and see how many consistant shots you get. Use the bottle gauge, not the one on the rifle.

The only way you will do better is to get it regulated..Ben Taylor. About 250 quid I think and TBH, for thos extra 20 shots per fill...is it worth it?

I think the rifle is performing exactly how it should.

Hope this helps.

[jamiedenny]

Hi,

 

thanks so much for the reply. I did warn that I was struck down by Chronostitis! :( .

 

Does the drop in over a ftlb not seem strange ?. Unfortunately the drop makes quite a diffrenec with the 40-50 yard shots. I'm confident to take shots at this range but it is on the verge of just under / over a mildot on my set up. With a dinky little .177 pellet its enough to stop me taking the shot.

 

I'm sure your right, my chronostitis has become chronic.

 

J

[jamiedenny]

The only way you will do better is to get it regulated..Ben Taylor. About 250 quid I think and TBH, for thos extra 20 shots per fill...is it worth it?

I think the rifle is performing exactly how it should.

Hope this helps.

 

BTW, your right. I'm sure the service is fantastic but for that price I might as well sell the s410 and buy a regulated 2nd rifle.

 

J

[turbo33]

Hi,

 

thanks so much for the reply. I did warn that I was struck down by Chronostitis! :( .

 

Does the drop in over a ftlb not seem strange ?. Unfortunately the drop makes quite a diffrenec with the 40-50 yard shots. I'm confident to take shots at this range but it is on the verge of just under / over a mildot on my set up. With a dinky little .177 pellet its enough to stop me taking the shot.

 

I'm sure your right, my chronostitis has become chronic.

 

J

 

No the drop isn't strange at all. Most manufacturers will stop at 11.5ft lbs as a margin of safety with different pellets, so you're talking of 0.75ft lbs. So again going to our 36 yd zero 11.5 ft lbs would give you 0.36" drop at 40 yds, and 10.7 ft lbs would give you a drop of 0.41 of an inch drop. A difference of 1.27mm!!! With the greatest respect for your shooting ability, 1.5mm at 40 yds would be more than equally matched by pellet weight/quality variation, wind etc. TBH 50 yds is pushing it imho if you're on live quarry.

Have you wound the mag up on your scope? As obviously the higher mag, the greater the distance between the mildots.Try it at 6x max. The most rifle /kills ratio I had was an AA Classic. It dropped everything out to 40yds. I had it from new and chrono'd it half way through and it was pushing out a max of 10.5ft lbs!!I only sold it as I wanted to go carbine. As regards selling it and getting a regulated one, by all means do so, we all like a new toy. But if you know your rifle has 40 or so bang on shots from a fill, why bother? I am sure if you fill to 165-170 you will have more than enough consistant/lethal shots per hunting trip...thats an awful lot of bunnies to carry back. And if you run out, go back to the car and top up

If you want some more views, go on the Air Arms owners club. They're a helpful bunch and have some good advice

Edited May 12, 2012 by turbo33

[jamiedenny]

Thanks Turbo,

 

I leave the scope at x6 mag almost all of the time. I have yet to not drop any quarry in any situation.

Maybe I'm looking for an excuse to get a new toy :-).

[turbo33]

Thanks Turbo,

 

I leave the scope at x6 mag almost all of the time. I have yet to not drop any quarry in any situation.

Maybe I'm looking for an excuse to get a new toy :-).

 

 

Now you're coming clean HW100, carbine in .177 :good:

[jamiedenny]

where?, where?.

Me wanna.

 

:good:

[poguemahone]

something not right there mate. should be able to get 50 shots with a 10fps spread from a 400/410.

i'm 99% sure the problem is hammer/hammer rail related or the valve is sticking.

empty the gun and strip it down. check that the hammer runs VERY freely on the rail. if it doesn't it could be the slightest bit of oil,grease,crud etc on the rail. could need a rub with mega fine wet n dry and polishing and check the bush in the hammer isn't worn.

then check that the valve isn't sticking. it should drop VERY freely into the firing pot. when they've been hit by the hammer thousands of times they can distort/bend. if a polish with very fine wet n dry doesn't get it running freely you may need a new one. be careful not to damage the valve seat when polishing. also well worth polishing the ends of the hammer and valve springs with fine emery cloth before re assembling.

pm me if you need owt.

[funkey monkey]

prehaps you should of bought an r-10

[jamiedenny]

Hi,

 

Thanks so much for the reply. The more I test and play with it the more I'm sure there is something a bit strange. By re-filling to different pressures I can prove the "sweet spot" doesn't really exist. Its just inconsistent at any pressure with the first few shots reading much higher than the following.

I have already made sure the hammer and hammer rail are super smooth. I barely have to tilt the rail when the hammer is on it to get it running down smoothly. The only thing I didn't check was the valve as I haven't gone that far before.

Interestingly I also found the o ring (that sits between the vavle and the top part of the action with the barrel) looked a little worn so I have ordered some replacement seals.

I have sent you a pm if thats ok. I want to check I'm fiddling with the right bits.

 

J

 

prehaps you should of bought an r-10

 

Na, they only appeal to cow wrestling farm folk.

[jamiedenny]

something not right there mate. should be able to get 50 shots with a 10fps spread from a 400/410.

i'm 99% sure the problem is hammer/hammer rail related or the valve is sticking.

empty the gun and strip it down. check that the hammer runs VERY freely on the rail. if it doesn't it could be the slightest bit of oil,grease,crud etc on the rail. could need a rub with mega fine wet n dry and polishing and check the bush in the hammer isn't worn.

then check that the valve isn't sticking. it should drop VERY freely into the firing pot. when they've been hit by the hammer thousands of times they can distort/bend. if a polish with very fine wet n dry doesn't get it running freely you may need a new one. be careful not to damage the valve seat when polishing. also well worth polishing the ends of the hammer and valve springs with fine emery cloth before re assembling.

pm me if you need owt.

 

I'm not sure if this helps with the fault finding but I have fitted a mainspring from an FAC s410 and the results are lower. Makes me believe it is an issue with the valve. Back to the work bench it is.

[buster321c]

prehaps you should of bought an r-10

 

 

Yes then you could have had a load more problems aswell

[jamiedenny]

pow

[funkey monkey]

haven't herd of much problems with the mark 2 . well tbh can only speek for my own experience with it (prehaps ive had a good one (cross fingers))

.

[Clubshot]

I have a AA400 in .22 - around ten years old -

 

Have you tried different pellets - even a different batch No.

 

As well aware it does effect outcome -

 

Most AA's leave factory around 10.5 FP - Part of there current AT Policy

 

BOB/R

[poguemahone]

I'm not sure if this helps with the fault finding but I have fitted a mainspring from an FAC s410 and the results are lower. Makes me believe it is an issue with the valve. Back to the work bench it is.

if it isnt an issue with the valve it soon will be :lol: put your standard spring back in. pm sent.

[jamiedenny]

if it isnt an issue with the valve it soon will be :lol: put your standard spring back in. pm sent.

 

Ha, I know, I know.

Just interesting that there was no change in the output. Thanks for the PM, really helpful. The valve etc.. all needed a damn good clean. I had to push the thing out with a hex key!. A bit of gentle smoothing with wet and dry paper and it feels much better.

 

Chrono when I have time this week. I'll report back.

[jamiedenny]

Also if anyone knows how to edit the title of a post please let me know. My damn typo is annoying me now