Spa Pr900W Transfer Port

[bsasuperten 74]

morning lads just purchased this chinese pcp i know it's not in hw 100 league but at the price i could buy 4 of them to 1 hw 100 so shipped fron europe arrived had a test fire loud stripped it it had the larger transfer port fitted 3.2mm as high power not the uk spec 1.4mm 12ft lbs joby so is there any advantage in chamfering the transfer port from air reciever side towards the barrel inlet just to aid the airflow the same amount of air is released every shot so depending on hole size the power is vaiable but the same number of shots per fill is constant but the air is strangled with the littler hole in anybody got thoughts on this bsasuperten

[bsasuperten 74]

all sorted now transfer port drilled to 1.7 mm chamfered with 45 countersink and running at 11.47 with 8.4 jsb exacts

tried it out last night on my perm was quite supprized at how accurate it was probably 40 good shots nice and light so at £200 i think it's a bit of a bargain

bsasuperten

[stealthy1 3,964]

Put some pix up.

[stecorr 75]

yeah, lets have a look at it.....curious here

[bsasuperten 74]

sorry lads can't do pic's dont know how to

bsasuperten

[Pete tree 0]

Hello. Is your pr900 a .177 or .22? And does anyone know if transfer port size varies for the two? I know 177s let out more air per shot to give the speed needed for similar power despite lighter pellets (hence lower shot count in 177s usually).

I've just bought a 177 and I like it. Only used it for couple o of hours, but seems to give 4 full magazines (36 shots) with very little variation in speed, and no aim point changes at medium ranges, from ~190 - 150 bar fill (according to on gun manometer).

My only complaint is that it's spitting most pellets out at between 9.5 - 10.5 ftlbs (depending which pellets). And I'm inclined to tweak it up to ~11.5 if I can. Perhaps widening the air transfer port as you describe ?

Shouldn't change the shot count as I understand it.

[bigmac 97kt 13,786]

Here you go bsasuperten

 

[mark williams 7,551]

First glance and SPAPR900W would get called "Sparrow" by me .

                    I have mentioned this gun before with my RFD mate testing one at the range if you may remember ?

                    He had nothing but praise for it and what you get for your money, saying that the lads found it very accurate ( one inch groups) and producing 10.5 ft/lbs with AA Fields .177 straight out of the box and would/ should, rise in power a tad, as you run it in somewhat.

                    The lads said as a mid range hunter - just fine, they also said a little tinkering would transform it.

                    I have shouldered and dry fired this rifle in the shop, - quiet report, very comfortable and very light indeed.

                    So, the general thoughts were you could not get much better for £219 - brand new, and a good gun smith could easily improve  it.

[just-A-snap 1,269]

If happy with results from any Air Rifle, then who can ask for more?  As for the price.  Not even the cost of a good night out for two with food in London.  Years of good use or a few hours out with ejecting content the next day?  MMMMMM?

Enjoy bsasuperten

All the very best

[mark williams 7,551]

Just a thought -  didn`t "U" - Underdog hunt with one of these Sparrows and also a co2 one - to good effect if I remember rightly ?

[Rez 4,961]

4 hours ago, mark williams said:

Just a thought -  didn`t "U" - Underdog hunt with one of these Sparrows and also a co2 one - to good effect if I remember rightly ?

Beat me to it. Yeah, he used/uses one.

Handsome looking rifles they are indeed. 

[Outback 1 26]

Aaaah the word tinkering .

Cheers

[Baldcoot 2,352]

Bargin PCP only 180 quid at Ray buys n Sells in Brummigum,says 650fps for the .177 and 550 fps for the .22 .The .22 has a 7 shot  and the .177 9 shot magazine.Looks nice and i would imagine tuned they can hold their own ,the chinese are learning well just as the Japanese did with cars and bikes and we all know how that turned out.

[Pete tree 0]

Mine was £180 too (with a free tin of pellets) here in sheffield, and shooting 750fps with mid weight 8.4gr AA fields or of the box - which is 10.5ftlbs.

Cracking little rifle.

[R3AP3R1974 0]

On 18/05/2017 at 09:04, bsasuperten said:

morning lads just purchased this chinese pcp i know it's not in hw 100 league but at the price i could buy 4 of them to 1 hw 100 so shipped fron europe arrived had a test fire loud stripped it it had the larger transfer port fitted 3.2mm as high power not the uk spec 1.4mm 12ft lbs joby so is there any advantage in chamfering the transfer port from air reciever side towards the barrel inlet just to aid the airflow the same amount of air is released every shot so depending on hole size the power is vaiable but the same number of shots per fill is constant but the air is strangled with the littler hole in anybody got thoughts on this bsasuperten

Hi was it a 22 or 177, I ask as I have a 1st gen pr900w, and when resealing it I noticed the t/port had been played with and when fired through a crono it's up at 19.6ftlb so the range\club took the port out and binned it.. So not sure what size I need for my 22.