Deciding to change caliber can be a very hard decision to make,you spend years of practice knowing your ranges,you get to know the hold under and hold over to such a degree of accuracy that it becomes second nature, and you dont think about the shot,its there in your head,a built up graph on your points of impact,so when the thought to turn my rapid7 to .177 from my usual .20 started circling in my head i had to sit back.I weighed up all the pro`s and cons,looked at my rifle and thought she is never going to be the same again,it was like i was pulling her guts out,she had served me well , it was a long hard scary decision but one i am hoping proves right.
Heres my account on changing caliber`s over on my rapid7 and how the first session went with it.
The first thing to think about when doing the calibre change is the new barrel,are you going to buy new or second hand.The only trouble with buying second hand is you never know how good its going to be,you think why is he selling it,does it shoot like a shot gun.The same could be said about my barrel, but with being on a few shooting forums and helping out on the rapid7ownersclub you soon get to know a few lads that can shoot and the trust builds up between members,so the decision to buy second hand is made easier.
When changing the calibre on a rapid 7 it not just a case of taking your barrel off and slotting the new one home,there is also the pellet probes to think of ,all calibers have different sizes as the pellets are bigger and deeper in different calibre`s so the probes will be longer for say .177 and shorter for .22.
If possible you will be better off getting the probes that fitted the barrel in the first place if buying second hand as the faces will be matched and should be a snug fit.If your doing a change on some other pcp the probes are usually sealed by orings so this isn`t as critical as a rapid7 so you could buy straight from the factory and not have the headaches with sealing as you can get with other guns.
The next thing to weigh up is the magazines,at £50 a go is it cost effective to do all this and it not work for you,granted you can buy second hand again but at £30-35 for them it could pay to buy new for what extra it does cost.
I decided to advertise on the forum to do a calibre swap,this way i knew everything i got was matched up and hopefully if the barrel i got shot straight everything els would go smoothly.
It didn`t take long for a swap to be arranged,luckilly for me a member with two guns in .177 wanted to try the .20 and as he lived locally there was no worries of losing parts in the post and we could both see what we was getting condition wise.
The swap went smoothly on the day and it didn`t take long for me to get my bag of bits and start putting the rapid back together.
While i was reasembling my gun i decided that a complete overhaul was on the cards, so i changed all the orings and polished parts that i knew would make it run smoother once back together.
Now with all the bits back in order it was time for a chrono test.This went well it was shooting pretty consistent and a couple of tweaks on the reg had it shooting a nice 11.4ftlb and a 5fps variation over 34 shots.Thats more than i could have hoped for considering 2 hours before it was a .20 .
Next it was a zero session.I started off using AA field weighing 8.4 grains it took a mag to get it zeroed but it wasn`t as accurate as my .20 , no need to panick here as no barrel likes every pellet,so off to the cupboard and get some webley mozzies.These are 7.9 grains and to be fair i like a lighter pellet just to get the shot as flat as possible.
Now we were talkin,this barrel loves the mozzies.Once zero was found i shot two mags in a target at 20 yards and the hole was smaller than a 5p now thats what i call accurate, 34 shots and everyone a killer.
Next i decided to go up the farm and try a further zero at 30yards it shot just the same ,50 yards was a ragged hole with the odd one going off due to me not trying so hard with the very slight breeze as it seemed to just hit the target itself.
Well i decided to have a walk round a couple of fields while i was here ,just incase something decided to show itself.Half hour later still walking round and nothing ,it had snowed ,hailed and was now raining so i decided to call it a day and headed off back to the car.Just before i got back i noticed something sitting under the hedgrow about 70 yards away , a quick scan through the scope confirmed a rabbit.Between me and the rabbit was a water tank for the cattle so i squatted down and started the slow crawl to the tank.Now this is not recomended for anyone with bad knees as i could feel the water soon getting through my trousers and my gloves, by the time i had got 30 yards to the tank my knees were frozen ,they were so numb but this rabbit was going to be the first kill for the .177 so i wasn`t bothered.
Looking over the tank i could see the rabbit ,he was looking slightly away from me so made it easier to slide the gun ontop of the tank and get into a comfortable position to aim.I put the cross just the side of his ear and gently pulled the trigger,not taking my eye from the scope i watched him roll over and that was curtains for him.What a start one shot 1 kill.
When i got to him i noticed the tell tale signs of mixy,no wonder he was out in this weather, all i could think was could i have got closer without going on my bloody knees and getting soaked.Maybee , maybee not ,knowing my luck it would have ran off ,this way it was put out of its misery and was suffering no more.