Author Topic: Blerk's Progress  (Read 37358 times)

0 Members and 3 Guests are viewing this topic.

Offline Gambo

  • Administrator
  • SuperHero Member
  • *****
  • Posts: 28359
  • Karma: +215/-50
  • Pellet Porn Queen
    • Cardiff, South Wales.
Re: Blerk's Progress
« Reply #540 on: October 12, 2017, 08:02:45 PM »
Hmmmm, the legal limit using those weight pellets is 606fps, so you are well down on that Blerky.

However, JSB's 15.9gr pellets are usually the most efficient, and the velocity limit for those is 583fps, but I prefer to set the rifle between 570 - 575fps (11.6ftlbs), to give a safety margin to remain legal.

Offline IceBlerk

  • Hero Member
  • *****
  • Posts: 1371
  • Karma: +331/-7
    • Sheffield (Just a little South of it, across the border into Derbyshire)
    • My YooChoob Channel
Re: Blerk's Progress
« Reply #541 on: October 13, 2017, 07:24:14 AM »
I called the shop yesterday. They'd replied to my email and said to call to discuss options.

Their response was more or less what I expected; bring it in, put it over their chrono and take it from there.

They said they MIGHT be able to do something there and then (which would be good but I have my doubts) or they'll send it back for fettling at the factory (which could take a couple of weeks but nothing is certain).

* Sigh * ......... As I'd rather not be without my rifle for any length of time I asked if the end of November would be OK (as I'm away on holiday then) and they said it would.

So it looks like I'll be trekking up the road with it in a month's time.

They DID suggest that I chrono it after some shots had been fired through it rather than immediately after a fill and that sounds perfectly reasonable BUT I'd be surprised if the climb up the start of the power curve is steep enough to get an additional 1 1/2 ftlbs out of it.
..........so I packed up and went to the pub.

Offline Baggawind

  • Hero Member
  • *****
  • Posts: 1324
  • Karma: +150/-4
  • Planet Airgun's Pied Piper
Re: Blerk's Progress
« Reply #542 on: October 13, 2017, 02:42:24 PM »
Oh but it  can mate. Your Bantam is un-regulated therefor will have a pronounced power curve. All un-regged guns when filled to the manufacturers maximum fill pressure will be well down on power. Try filling it to say, 150bar - the sweet spot for most un-regulated guns, then increase the pressure by 10 bar then test it again and repeat the process until you see a marked decrease in power. Just below that pressure will be your ideal fill pressure. The sweet spot on most Air Arms rifles will start at 170 bar, give or take. Fill it to 190 and it will be around 1 1/2 fpe down. All the ones i,ve tested, including my own have done so. I picked up an almost new AA s400 for a friend and when we tested it the sweet spot started at 155bar !!? and went right down to 80bar before dropping off.

Offline seagate

  • SuperHero Member
  • ******
  • Posts: 5967
  • Karma: +179/-22
    • Wakefield The Garden of Eden
Re: Blerk's Progress
« Reply #543 on: October 15, 2017, 06:42:02 PM »
If your using Kaiser pellets 14.6grn made by HN, weigh them just to make sure they weigh that. I've experienced HN pellets with a claimed 14.6grn actually weighing 15grn.
I plink , therefore I am.

Offline IceBlerk

  • Hero Member
  • *****
  • Posts: 1371
  • Karma: +331/-7
    • Sheffield (Just a little South of it, across the border into Derbyshire)
    • My YooChoob Channel
Re: Blerk's Progress
« Reply #544 on: October 16, 2017, 10:55:07 AM »
I went to the range on Friday evening and I planned to chrono my gun at a much lower pressure. Lowering the pressure is quite an exercise in itself given that the manufacturer promises c250 shots per fill.

As it happens I was off to a non-starter anyway; someone had shot the chrono and it was out of action (RIP).

So I decided to have a little plink and see how falling pressure affected my zero.

Do you recall that I'd had ishoos trying to zero my gun? I'd been twisting the turrets like a nutter?

I still wasn't 100% happy with it so I thought I'd investigate how pressure affected things.

Here's a pic of a metal target (about 25cm x 25cm) I was using to zero at 25 yards:



I was trying to get groups in the centre and at "12 o'clock", "3 o'clock", '6 o'clock" and "9 o'clock'.

No, really, I was!

Bloody hopeless, eh?

I kept trying at various ranges and the results were consistently crap. I was starting to question the gun. More shots at more targets at various ranges and no groups were forming.

And then, from out of nowhere, I had an idea.

I removed the silencer.

Here's a pic of the first attempt at zeroing at 25 yards without the silencer (groups of 5):



Can you see the subtle difference? The slight improvement in grouping? The improvement in consistency?

OF COURSE YOU CAN!!!!! Look at the bloody thing! It's a world, no, a galaxy of difference from the first one.

The gun doesn't like the bloody silencer (I should have guessed at that, it came from Welsh Wales!). Unfortunately I didn't have either of my other guns with me to try the silencer on so I don't know if it's an ishoo with it or the rifle not liking it. And I didn't have my other silencer with me so I couldn't try that on the Bantam either. So I still have a bit more experimentation to do.

Oh! I nearly forgot! I made like an Eskimo with bestial tendencies on Friday too; I blew a seal!

Now, I know how it happened and, thanks to the entertaining Giles Barry of the excellent  Airgun Gear Show I knew that blowing a breach seal on a Bantam was always a possibility. I also knew that fixing it was a task I shouldn't be scared of.

So I cracked on and re-seated the seal.

I didn't do it correctly (of course) and ended up with a pellet lodged in the barrel and having to do it a second time.

Which I did and, I'm pleased to say, did a far better job second time around.

Here's a third target at 25 yards after my "repair" :



That's two groups of ten. The one at 12 o'clock is me, no silencer, using the scope. The one at 3 o'clock is me, no silencer, using the camera and screen of my NV rig.

So, what have I learnt?

  • Many pieces of hardware can affect accuracy and consistency. In this case it's the silencer.
  • The gun is good. Even in my hands it is consistent.
  • My groups are tighter when I use the camera and screen. And from that I deduce that my shooting position is inconsistent and parallax (or whatever) is affecting my shots.
  • I need to get a chrono so I'm not relying on the one at the range.
  • I've put about 120 shots through the gun since filling it and I still have a half full bottle. The promised c270 shots per fill may be true.

None of this would be worth doing if it was easy, eh?
..........so I packed up and went to the pub.

Offline Gambo

  • Administrator
  • SuperHero Member
  • *****
  • Posts: 28359
  • Karma: +215/-50
  • Pellet Porn Queen
    • Cardiff, South Wales.
Re: Blerk's Progress
« Reply #545 on: October 16, 2017, 04:26:02 PM »
It was for that very reason that when you had my Hatsan, I sent you the silencer (a BLOODY expensive one at that!) which I knew for certain would fit on that particular rifle without compromising accuracy.

Some makes of rifle don't like certain brands of silencer, and sometimes a model of silencer will work perfectly on one given gun, but a supposedly identical silencer won't!! At the end of the day, it's all down to trial and error, and/or experience.

So your comment of......"Many pieces of hardware can affect accuracy and consistency" is absolutely true.


Out of interest, what brand of silencer were you using Blerkster? ???

Offline rabbit sniper

  • Moderator
  • SuperHero Member
  • *****
  • Posts: 11201
  • Karma: +617/-287
  • .22 for men .177 for girlies
    • rochdale
Re: Blerk's Progress
« Reply #546 on: October 16, 2017, 10:40:07 PM »
Was the palm trees swaying and the waves gently splashing up the beach while you were blowing that poor seal  ;D
Otherwise known as Rabbit Sniffa AKA Cougar Hunter

Offline IceBlerk

  • Hero Member
  • *****
  • Posts: 1371
  • Karma: +331/-7
    • Sheffield (Just a little South of it, across the border into Derbyshire)
    • My YooChoob Channel
Re: Blerk's Progress
« Reply #547 on: October 17, 2017, 08:00:36 AM »
Was the palm trees swaying and the waves gently splashing up the beach while you were blowing that poor seal  ;D

Lol! They were swaying last night in the Ophelia's breeze!

Out of interest, what brand of silencer were you using Blerkster? ???

It's the one I got from you with the Hatsan. QSG is it?

I'm going to put it back on the Hat and see if it's just doesn't like the Bantam or if it's become damaged in some way.
..........so I packed up and went to the pub.

Offline Gambo

  • Administrator
  • SuperHero Member
  • *****
  • Posts: 28359
  • Karma: +215/-50
  • Pellet Porn Queen
    • Cardiff, South Wales.
Re: Blerk's Progress
« Reply #548 on: October 17, 2017, 09:28:28 PM »
FYI y'all......jus my opinion like.....

Once I have found a suitable silencer for a given rifle, one that is very effective as a sound reducer and doesn't compromise accuracy, then that's where that silencer spends the rest of it's life.....forever. Period.

Never ever are any of my silencers swapped from rifle to rifle.........you wouldn't dream of swapping a scope back and forth between rifles whenever you wanted to use one of 'em, and I would suggest the same should thinking should be applied to silencers.

Just as certain brands of scope mounts suit certain brands of airgun rails better than others, then so it is with silencers. Some barrels are thinner or thicker than others, and it follows the mating face of some silencers are different too....some are chamfered, some are not, some are skinny, some are thicker. Therefore, it's easy to understand why some designs of silencers don't suit some designs/sizes of barrels.

If an unsuitable barrel/silencer combination a used, pellets will become unstabilised as they pass too close to the internal baffles or endcap, or in a worst case scenario will actually clip the baffles or endcap, as the silencer won't be sitting perfectly square/parallel to the bore.

After the correct safety procedures have been taken,t his can be checked by eye by shinning torchlight down the bore from the breech end, and then silencer/bore alignment checked by viewing through the silencer from the muzzle end. Obviously a break barrel rifle can be simply inspected from the breech end.

Another method is to use a cleaning rod inserted through both the silencer and barrel.

If the bore of the silencer doesn't align with the bore or the barrel, it will be immediately evident, and the only option (without getting into the realms of machining) is to try another silencer until one is found that does align perfectly.


Frustrating, Yes......but not half as frustrating as pulling your hair out coz your pellets won't go where you want them to!!

Offline IceBlerk

  • Hero Member
  • *****
  • Posts: 1371
  • Karma: +331/-7
    • Sheffield (Just a little South of it, across the border into Derbyshire)
    • My YooChoob Channel
Re: Blerk's Progress
« Reply #549 on: October 25, 2017, 01:05:49 PM »
I took my Bantam to my local shop last night.

It was down to about 100 bar so I thought a bit of chrono time was in order.

At that pressure it was still giving out about 10 ftlbs. Laddo topped it up to 192 bar and popped it back on the chrono. c10 ftlbs again.

So, it looks like my rifle is putting out c10 ftlbs on "Maximum" setting.

"You could try a heavier pellet," says laddo. And I appreciate what he's saying BUT ............... Brocock's recommended pellet is the 14.66gr Kaiser so I think I should be able to achieve c11.5 ftlbs with that one.

Am I being unreasonable?

Anyway, later that evening, after I'd done a bit of decorating and fed the youngest lad, I went took my kit out.

Rain interrupted my ratting so I moved from my first perm to The Grain Factory knowing that if the rain continued there is a covered barn area. Needless to say, the rain didn't ease so I ended up in the barn and did a little plinking while I waited for rats.

To test accuracy and PRACTICAL power I placed a concrete block at 15 yards. I put 10 shots into The Block and here's the result:



An even more close-up pic :



Apologies for the quality of that pic.

I appear to have 2 groups (I can only blame the quality of my shooting); one has resulted in a divot of concrete being removed from the block and, just above that, one has pellet on pellet lodged in the block.

"Why are you rambling on about this, Blerk?" I hear you ask.

It's a reasonable question.

I wanted to reassure myself that my rifle is accurate and powerful enough for humane ratting (and possibly bunny blasting).

The above pic shows that it HAS the accuracy and consistency and, with constant practice, I'm confident that my ability will improve and one day I'll be able to take a pic of a concrete block with even better results on its surface.

But has it got the power? Well ........ it hasn't got the power that is written on the side of the box with the pellets I'm using but it's got enough power to batter into concrete and that's enough power to do the job right now.

So I'm going to stop fretting. I'll take it back to the dealer and have him tweak it but I'm in no rush. As I've said previously, I'll wait until I can do without it for a few days.

In other gnus; I'm shopping for a new silencer for the Bantam. Does anyone have any recommendations?

I'm also putting together my birthday/Christmas list. So far I have the following items on it:
  • CB-625 chronoscope
  • An extra magazine for my rifle
  • Rifle sling, swivels and studs
  • Variable power IR torch
If anyone can recommend sources, brands, models, bargains for any of the above please let me know.

If anyone can recommend any other items let me know about those too.

Laters!
..........so I packed up and went to the pub.