Power Question.......help Needed Please !

[deanothehunter 34]

I been using a stoeger x20 springer with good results until i get a new pre charged, but even when I bought it a year or 2 ago it only was doing about 10 1/2 ft lb out of the shop but out to my 35 yrd max range it still had plenty of thwack against rabbits and closer stuff like woodies and squirrels.

 

Since that time its slowly got less power probably due to main spring wear as they do, but I chrono'd it earlier and its around 10.3 ft lb but it still has energy at max range to cleanly take a rabbit which i been told only takes 3 to 4 ft lb to do but was wondering what would be the minimum muzzle energy required for a clean kill out to 35 yrds, for instance would a gun shooting at 8ft lb still retain enough energy out to this range.

 

Is there a chart to explain retained energy at various ranges etc with different muzzle velocities ?

 

Cheers,

 

Deano

[kruby01 114]

I have the stoeger aswell mate and its a great gun for the money. mine still has power for rabbits at 35 yards but if yours is still at 10 it shouldnt need a spring maybe just a strip down and clean re grease etc? Out of curiosity what pellets are you using with it?

[WoodsmanJim 160]

Chairgun will tell you retained energy at all ranges. It's free to download from the Hawke website. My friend has a rifle at 8.5 ft/lb and it retains something like 70% energy at 30 yards, I can't remember exactly but it was still way more than 4ft/lbs at 30 yards. I'd still recommend having as much power as legally possible to make cleaner and easier kills though.

Jim

[deanothehunter 34]

I been told best pellets in pre charged are heavies and very light in springers, the lightest ones i found are Falcon accuracy plus at 13.43 grains and they are very good in this gun, my last pre charged was .20 cal and was using jsb exact at 13.73 grains so even the smaller calibre pellets were heavier than these but they are pretty good and being lighter give better fps etc

 

Deano

[kruby01 114]

I use RWS superdomes in mine I think they are 14.9 off the top of my head. Just ordered another tin as they group well and seem to do well at longer ranges

[deanothehunter 34]

Chairgun will tell you retained energy at all ranges. It's free to download from the Hawke website. My friend has a rifle at 8.5 ft/lb and it retains something like 70% energy at 30 yards, I can't remember exactly but it was still way more than 4ft/lbs at 30 yards. I'd still recommend having as much power as legally possible to make cleaner and easier kills though.

Jim

 

I have that chairgun on laptop but cant quite work out things like scope height etc is that height from scope rails to bottom of tube, or rails to centre ? or top of scope ....

 

Also Im hoping to get new gun soon in .20 but it does'nt seem to have .20 on there just .177, .22, .25 if it can be changed for each pellet not found how to use yet lol

 

Cheers,

 

Deano

[PaulEamonn 37]

Hi Deano

 

According to my calculations on Chairgun Pro, you can go all the way down to 6ft/lbs and still be getting 4.4ft/lbs of energy at 35yds with a 13.4g pellet. Though I suspect that would be the total minimum you'd want to go to as I've heard that it can take between 4-6ft/lbs to get through a bunny's skull. 8.5ft/lbs may be a better minimum to not go below and that will give you 6.3ft/lbs at 35yds.

 

Regarding weight of pellet. As I understand it (and have seen on my own chrono), heavier pellets put through a PCP will record a higher ft/lb reading than when using lighter pellets. However, the reverse is true when chroning a springer. You'll get a higher ft/lb reading using lighter pellets. I used to use RWS Hobbys in my springer and they did the job out to 35/40yds.

 

Why this happens, I know not but I'm sure there is some far better educated person out there who can enlighten us.

 

FPS isn't the best way to judge a pellet. It's the energy that it imparts at its destination that's important. If it's going too fast, there is a higher chance of over-penetration that may not result in a clean kill. That's one of the reasons why I used Hobbys (apart from the fact that my old springer liked them). They were light - so gave a high energy/fps and they were flat headed - so most of the energy was released on impact.

 

As for your question about scope height. I was unsure of this too so I emailed Hawke and they came back and told me it is the measurement from the centre line of the barrel to the centre line of the scope. Makes sense really, doesn't it? After all, those are the two points we are trying to ascertain the relationship between.

 

You really ought to go to the effort and learn how to use Chairgun Pro. It's quite a good bit of kit. If you get stuck, post up here. I'm sure someone will be able to help out.

Edited May 9, 2013 by PaulEamonn

[ghillies 209]

no need to worry about 10.5fp's... i was using it for months out to 55 odd yards on rabbit.(an exellent set up though..gun wise).

[deanothehunter 34]

Hi Deano

 

According to my calculations on Chairgun Pro, you can go all the way down to 6ft/lbs and still be getting 4.4ft/lbs of energy at 35yds with a 13.4g pellet. Though I suspect that would be the total minimum you'd want to go to as I've heard that it can take between 4-6ft/lbs to get through a bunny's skull. 8.5ft/lbs may be a better minimum to not go below and that will give you 6.3ft/lbs at 35yds.

 

Regarding weight of pellet. As I understand it (and have seen on my own chrono), heavier pellets put through a PCP will record a higher ft/lb reading than when using lighter pellets. However, the reverse is true when chroning a springer. You'll get a higher ft/lb reading using lighter pellets. I used to use RWS Hobbys in my springer and they did the job out to 35/40yds.

 

Why this happens, I know not but I'm sure there is some far better educated person out there who can enlighten us.

 

FPS isn't the best way to judge a pellet. It's the energy that it imparts at its destination that's important. If it's going too fast, there is a higher chance of over-penetration that may not result in a clean kill. That's one of the reasons why I used Hobbys (apart from the fact that my old springer liked them). They were light - so gave a high energy/fps and they were flat headed - so most of the energy was released on impact.

 

As for your question about scope height. I was unsure of this too so I emailed Hawke and they came back and told me it is the measurement from the centre line of the barrel to the centre line of the scope. Makes sense really, doesn't it? After all, those are the two points we are trying to ascertain the relationship between.

 

You really ought to go to the effort and learn how to use Chairgun Pro. It's quite a good bit of kit. If you get stuck, post up here. I'm sure someone will be able to help out.

Cheers yeah does make sense, will have a look later tonight and have a play with it

 

Deano

[gasman1 15]

10.5 is plenty of power for hunting. as long as you can get the pellet to hit the right spot, it'll do the job easy.

[hunter100t 56]

8.5 ftlb is great if you want your quarry to hear it coming before it is half way, on the other hand, you could make sure they dont by keeping your rifle somewhere near the legal limit, thus ensuring a clean kill and not wounding the animal. or if you dont want the recoil, get it tuned near the limit, or get a pre-charge.

lowering your power to not far above pistol limits is not the answer.

 

atb phil

[deanothehunter 34]

Cheers everyone, I want it to be nearer the limit but not too near as even a simple new mainspring can bring them up way to much then all the pellet and chrony testing i just cant be doing with tbh.....

 

Deano

[hunter100t 56]

When you put a new mainspring in, It will need re testing and adjusting if necessary anyway.

 

atb phil

[-Lupo- 4]

The Stoegers have problems with the poston seal after a while. The original one is not the best.

 

I recommend to put in a seal of the Gamo 440 Series or one of the Tell (Cometa) Fusion/400.

 

Best seal for the Stoeger, i use this seal in my own X20S and it has got a little more power just because of this seal.