.177 slugs in a FAC Rapid

[etiam viviens]

I have a Rapid with a 650 mm .177 barrel without a choke that does a potent 55 joule with the H&N Piledrivers.
while the groeping is not to bad the results are acceptable. but they stopped making them and I need an alternatieve.

using the 10.3 JSB it goes super sonic so that is not an option. And I have ordered some ZAN 20 and 24 grain slugs and was wondering if someone are allready using these with good results

[angrybear]

If it goes supersonic with the JSB 10.3's why not just turn the power down a touch to keep it subsonic 
I've never quite understood the "extra heavy pellet to cope with all the power" argument.

I've tried the Zan slugs in .20cal 15gn but only sub 12fpe, they seem excellent out to 25 yds, ragged single hole,
but then they suddenly go haywire, I suspect velocity drops too slow & maybe need more twist rate

[etiam viviens]

I'm punching paper or ringing gongs / hitting spinners at 100 and want to extend it to 200 meters.
And we in Holland have no limit on power, so there is no need to reduce power.

I was hoping someone has some experiance with this.

[DRT.1]

Im headed down the same path albeit in .22 and a very early MK1 Rapid thats been serviced by KevG and had his power plenum added. The barrel is one thats lurked in the workshop and I think is an HW one measuring 23" long. With 18gr pellets its running at 44ft/lbs ( no reg) on a 220bar fill. Id be very interested to hear more detail from those using slugs on what barrels/speeds slug weights they are using and also what twist rate the barrel of choice is?

[skagitmonster]

I have a Rapid with a 650 mm .177 barrel without a choke that does a potent 55 joule with the H&N Piledrivers.
while the groeping is not to bad the results are acceptable. but they stopped making them and I need an alternatieve.

using the 10.3 JSB it goes super sonic so that is not an option. And I have ordered some ZAN 20 and 24 grain slugs and was wondering if someone are allready using these with good results

I've ised mako slugs in 177 at 900 fps in a standard choked lowther barrel that was 19 inch long and the groups were 5p at 50 yards,  stretching it out to 70 yards was no problem at all hardly any spread in grouping

[skagitmonster]

I have a Rapid with a 650 mm .177 barrel without a choke that does a potent 55 joule with the H&N Piledrivers.
while the groeping is not to bad the results are acceptable. but they stopped making them and I need an alternatieve.

using the 10.3 JSB it goes super sonic so that is not an option. And I have ordered some ZAN 20 and 24 grain slugs and was wondering if someone are allready using these with good results

I've ised mako slugs in 177 at 900 fps in a standard choked lowther barrel that was 19 inch long and the groups were 5p at 50 yards,  stretching it out to 70 yards was no problem at all hardly any spread in grouping

that was from a mk1 I need to add , a double tap setup and regulated , if I recall around 130 bar ...I think as it's been a few yrs ago but defo a standard choked lowther shot makes v well indeed ...barrel was done by nick but purchased from flyfisher

[skagitmonster]

It's the restricted nature of the mk1 that'll hold you back with slugs being 4mm ported ,mk2 6mm better and bung a reg in with a choked polygon as long as a walking stick 
As for slugs it'll be a trial , h and n , nsa etc you'll just have t keep trying snd you'll find one that suits as for speed 900 plus in 22 More like 950 plus ...hence the mk2 or modified mk1...or raw

[skagitmonster]

It's the restricted nature of the mk1 that'll hold you back with slugs being 4mm ported ,mk2 6mm better and bung a reg in with a choked polygon as long as a walking stick 
As for slugs it'll be a trial , h and n , nsa etc you'll just have t keep trying snd you'll find one that suits as for speed 900 plus in 22 More like 950 plus ...hence the mk2 or modified mk1...or raw

I'm talking about the action itself , mk1 internal porting is 4mm
Mk2 internal porting is 6mm
You can modify a mk1 to near 7mm ....but you'll need a good engineer to do it for you unless you can do it yourself ....both options I would regulate not fastflow

[skagitmonster]

It's the restricted nature of the mk1 that'll hold you back with slugs being 4mm ported ,mk2 6mm better and bung a reg in with a choked polygon as long as a walking stick 
As for slugs it'll be a trial , h and n , nsa etc you'll just have t keep trying snd you'll find one that suits as for speed 900 plus in 22 More like 950 plus ...hence the mk2 or modified mk1...or raw

I'm talking about the action itself , mk1 internal porting is 4mm
Mk2 internal porting is 6mm
You can modify a mk1 to near 7mm ....but you'll need a good engineer to do it for you unless you can do it yourself ....both options I would regulate not fastflow

apologies about bombing this post I can't seem to find the ( alter post tab )

[Kernal]

It`s called quick edit M8

See picture i`ve uploaded to you can see it

[DRT.1]

It's the restricted nature of the mk1 that'll hold you back with slugs being 4mm ported ,mk2 6mm better and bung a reg in with a choked polygon as long as a walking stick 
As for slugs it'll be a trial , h and n , nsa etc you'll just have t keep trying snd you'll find one that suits as for speed 900 plus in 22 More like 950 plus ...hence the mk2 or modified mk1...or raw

I'm talking about the action itself , mk1 internal porting is 4mm
Mk2 internal porting is 6mm
You can modify a mk1 to near 7mm ....but you'll need a good engineer to do it for you unless you can do it yourself ....both options I would regulate not fastflow

Making the MK1 breathe isnt that hard,..for power you need internal volume ( plenums will also help). To "get into" a MK1 its easiset if you put in the bottom MK2 style capped port,..u then have easy access to setup for internal machining,..just be concious of damaging the valve face area. This can free up considerable volume and flow. Still missing in the replies is anything about twist rates etc? Anyone else playing with choke/unchoked and poly barrels? Interesting to see more efforts with the 177 calibre slugs and clearly given that its easy to get them into the 900's speed wise, it seems to be paying off.

[flyfisher]

It's the restricted nature of the mk1 that'll hold you back with slugs being 4mm ported ,mk2 6mm better and bung a reg in with a choked polygon as long as a walking stick 
As for slugs it'll be a trial , h and n , nsa etc you'll just have t keep trying snd you'll find one that suits as for speed 900 plus in 22 More like 950 plus ...hence the mk2 or modified mk1...or raw

I'm talking about the action itself , mk1 internal porting is 4mm
Mk2 internal porting is 6mm
You can modify a mk1 to near 7mm ....but you'll need a good engineer to do it for you unless you can do it yourself ....both options I would regulate not fastflow

that was a Silco HW barrel that you bought from me bud.

[skagitmonster]

It's the restricted nature of the mk1 that'll hold you back with slugs being 4mm ported ,mk2 6mm better and bung a reg in with a choked polygon as long as a walking stick 
As for slugs it'll be a trial , h and n , nsa etc you'll just have t keep trying snd you'll find one that suits as for speed 900 plus in 22 More like 950 plus ...hence the mk2 or modified mk1...or raw

I'm talking about the action itself , mk1 internal porting is 4mm
Mk2 internal porting is 6mm
You can modify a mk1 to near 7mm ....but you'll need a good engineer to do it for you unless you can do it yourself ....both options I would regulate not fastflow

that was a Silco HW barrel that you bought from me bud.

shot makes bang on , my mistake i thought it was a standard lowther , no way to see as all the other forums info is gone , I've no doubt your correct though most likely my mistake , either way mako slugs in 177 out a polygon / silco  barrel and a standard lowther ( I've lotsa barrels) and in .22 a standard choked anny in sub 12 chucks h and n slugs not too shabby

[etiam viviens]

I do not have the habit to make pictures of my groups but this is a cutout of a picture that I send to a friend.

This is at 75 meter, H&N piledriver and no wind. 55 joule at 284 m/s.

Groupe size is about 3 to 4 cm

[DRT.1]

thats not shabby,..can u say more on the rifle build/ barrel/twist/probe/speed?