Help Please......with Brocock Concept .177 Power limit setting.

[tileman 0]

Hello, Anyone help via PM PLEASE, I Have a Brocock Concept that is only putting out 10ft/lbs so I phoned Brocock and basically they won't help, I told them it was set at 10 ft/lb and he said they set them low deliberately so they can't be blamed if someone is over the legal limit, he said to try Bisley magnums though it and they will chrono at 12.5 ft/lb, but if it's still low send it back to them.............................. that's brill.

Does anyone know how to adjust it or have any instructions?

 

I DON'T want this info so I can set the gun ABOVE the legal limit, I just want to get it nearer to the legal limit.

 

john

[AirgunGuy 362]

What pellet did you use for the chrono test? It must've been a light pellet or it will be needing adjusting.

 

I agree...you should do as he suggests and try the heaviest commercially available pellet which to the best of my knowledge is a Bis Mag/ Barracuda and take it from there. You should be looking for 11.5FPE with it

Edited October 5, 2012 by AirgunGuy

[tileman 0]

What pellet did you use for the chrono test? It must've been a light pellet or it will be needing adjusting.

 

I agree...you should do as he suggests and try the heaviest commercially available pellet which to the best of my knowledge is a Bis Mag/ Barracuda and take it from there. You should be looking for 11.5FPE with it

 

Hi AA Diablo Field 8.4 Grains

[AirgunGuy 362]

I'm more a .22 man but i would think that that pellet should give you a higher reading than 10 FPE. I would definitely try a some Bis Mags and take it from there

[tileman 0]

Thing is, I can't afford to have brocock or gun smiths doing what I can do, when I was working, I was a mechanical engineer, so I think I can manage the little bits that are on guns.

[AirgunGuy 362]

Understand mate but what you have to realise is that very few people will give out such information due to legislation, even as a PM. You could be anybody.

 

To the best of my knowledge, recently manufactured rifles have anti-tamper measures inbuilt so that they cannot be adjusted by anyone other than the manufacturer or someone with an in depth knowledge of a particular rifle.

 

Try a heavyweight pellet any see how it goes.

 

PS. My mate bought a new 97k and when i ran it over the chrono it was doing 10.5 FPE after he'd put a tin of pellets through it and it kills rabbits stone dead at 35 yards no problem. It is widely regarded that it only takes somewhere in the region of 4 FPE to kill a rabbit with a well placed pellet. Also, if you're rifle is putting out around 10 FPE at the muzzle then the velocity of the pellet will only have dropped a couple ft/lb's at 30 yards so i wouldn't be overly concerned

[robwelsh 354]

I had a gun that was shooting 10.6 with every pellet weight lol give or take. I still killed stuff outright. It then crept up the more I shot. It went up to 11.8 then. The birds nd rabbits didn't hit the ground any faster or harder. Infact you'll be quite supprised that its only a couple fps difference in comparison to the 600+ fps its putting out. You only need 2-3 ft lb to kill a rabbit. And a 10ft lb .177 will certainly do that at 40yrds. Plus, no one will help you here on adjusting power settings. An unless you remove or have anti tamper stuff the only way round it is if you send it back, but it'll come back at 10 anyway. Atb

[tileman 0]

Hi All, last week I tested the gun with the air pressure starting at about 190 bar pellets = Crosman ultra magnum 10.5gr and got 10.91, 10.98, 10,82, 11.72, 11.86. today with the same pellets, air pressure about 195 bar I got 9.11, 9.38, 9.49, 9.39, 9.49, 9.66, 9.61, 9.69, 9.84, 9.93, 10.03, 10.04, 10.13, it seems as the air pressure reduces the muzzle energy increases, but that can't be right or is it because the barrel warms up a little.

I am using a Combro CB-625 Mk4 about a couple of weeks old, could it be the Combro is faulty considering the difference from last week to this week.

John

Edited October 15, 2012 by tileman

[fry 209]

sounds like a 160 bar sweet spot like air arms just fill it to 165/70 bar simples.

[tileman 0]

sounds like a 160 bar sweet spot like air arms just fill it to 165/70 bar simples.

Hi Fry, How does lower air pressure = higher muzzle velocity.

[fry 209]

i dont know why mate i know it sounds daft but its true i only fill my 410 to 160 bar. some one who knows why will be along soon and tell you why no doubt. and if its new the power will probably rise after a thousand shots.

[neil82 1,087]

higher pressure in the tube makes it a bit harder to open the valve, plus the higher pressure closes it faster, you need to shoot a full string and map out the `sweet spot`

[AirgunGuy 362]

As above mate. You need to know where the sweet spot is and do a string. The sweet spot may be from 170 down to 100 or something like that. Above or below and it will be erratic. The Combro seems fine.

[barrywhite 282]

your gun may well shoot its highest at 130 ..140 bar..ish .

[tileman 0]

Hi All thanks for your replies, I have had another go and I filled again and took 5 shots at each pressure with the same pellets ......140 bar I got 11.44, 11.69, 11.62, 11.50, 11.46.......160 bar I got 10.98, 11.16, 11.20, 11.18, 11.03.......170 bar I got 10.39, 10.61, 10.48, 10.68.

 

So from 160 bar down it was giving about 11 ft/lb and rising as the pressure fell.

 

I will check what I get at 130, 120, 110 and 100 bar in the morning.

 

I feel the top reading of 179 ft/lb is a bit close to the bone, the thing is I can't adjust it and I am not sending it back to Brocock.

 

Does anyone know which pellet weight the police use to test.