I'm looking to get a new "engine" for my d48...

[barcabarca]

Hi all,

I'm looking to get a new "engine" for my .22 D48 in the next month or two.  Because of funds, I will install it myself.

I have a spring compressor and have worked on all my airguns before.  I can do simple lube tunes, polish spring surfaces and parts with a dremel tool, etc.. I have replaced piston seals, and shimmed breech seals. But that is about all of my experience.

My goal is to have it shoot around 23+ FPE.  This seems do-able according to all of the information I have seen from Straight Shooters, the Yellow, and here.

My current D48 in .22 is shooting at about 21.5 FPE with CPHP 14.3gr pellets.

My question is: am I more likely to get the result I want from a Vortek kit? for from a ZRT kit from Maccari?  I have seen "increased" numbers from Maccari and Vortek both.   I have also seen no increases in speed as well and even reported declines from Vortek.  No complaints about shot cycles from either brand.

My experience with Vortek kits in both my D460 and my R9, was that initially they were both very strong shooters, My D460 was up around 27 FPE (.22) and my R9 was around 14 FPE (.177), but after about 300 pellets, both declined about 10% -15% in energy.   

Would I have the same results with the Maccari kit?  Anyone know?  Is there anything else that I should be thinking about to acheive my result besides a good polish to the internal parts?

My goal is to have this be my primary hunting rifle to 30 yards.  My quarry would be Squirrel to Raccoon.  Bigger game at shorter distances of course.

Thanks,

A

[amb5500c]

1st off, I would shoot a heavier pellet. That alone will give you more FPE.
Richard

[barcabarca]

Richard,

Thanks for the suggestion.  I was under the impression that a heavier pellet would be bad for my rifle, possibly damage the springs.  What would be a good weight do you think.

Thanks,

A

[Clark]

While more expensive, there have been excellent results using Héctor Medina's o-ring piston.  You can buy them through Vortek for $125.  The upside of this higher initial cost is a superior shot cycle with the stock spring, it's designed to shoot heavier pellets and there is no maintenance required for about 50K shots.  Power tends to be up "there" but it will vary with each gun.

If you're interested there is lots of information on the DWC.

Clark

[barcabarca]

Thanks Clark. that sounds great, but a bit expensive at $125 or so right.    I noticed that some did not see an increase in power, but a much better shot cycle due to the increased mass of the piston.     I'll take a look at the DWC and see if there is anything that will sway me.  Thanks again

[Mark 611]

IMO the heavies pellet is the way to go for now like Richard said, if you've got the fpe you got now a 16 to 18gr pellet is what I be doing, the Diana's have a heavy enough spring to handle those weights of pellet, the wire dia is a .130 wire in that gun from the factory, if it was any smaller on the wire I'd be looking to up grade, I wouldn't worry about doing a tune to it until you have to other than a basic lube and deburr on the parts you can with that type of rifle and just shoot it! JMHO 

[Mpac]

If i'm not mistaken the rws's use the 128 wire in thier guns and vortek do have a 130 wire that i put in my 460 and it is a very strong spring.Shooting at soda cans at 35 yrds. the other day and i thought i was missing open site until i seen dirt flying just behind it,that can did'nt budge or move i was saying wow.

[amb5500c]

My 48 shoots the 18 gr. JSB pellets better than any other. That's all I use in that gun.
Richard

[RedFeather]

I'm hearing that Vortek has changed springs on the kits to address any fatigue issues.

[Bullit]

Yeah, I'd go to the 16 grain pellet route as well, if that's what you want.  But I feel you are getting plenty of FPE downrange according to your current muzzle reading that you posted.  The Diana is plenty powerful as is, without getting tough to control.  A couple FPE at the muzzle isn't gonna equate the same downrange. I vote with smooth everytime. JMHO. UcanDO!

[Escondido1]

My most accurate pellet at 22yds is the crowmags 18 gr 22...funny, but true. John in PA is tuning it currently with PG2 for smoothness and shot cycle......I don't need more power..it's loaded for bear....I do want accuracy which is enhanced by smoothness and shot cycle and trigger yada yada.....Den

[Onebaddj]

You should be good launching up to 18-19 gr 22 cal pellets. Ive shot 13-18.9's with my 350. I chose the 14.66 cause they work the best out of it. I get 23 fpe muzzle and 17 fpe at 28 yds with them and the tightest groups. Heavier pellets will carry more energy down range to the target the key is to find out which ones shoot the best out of yoir gun.

The vortek kits work awesome. One of the members ran a maccarri kit and a vortek kit is 2 350's. The vortek out performed it. Maccarri builds good product also. My big cat was left cocked for 2 weeks and lost no velocity. Still shoots in the low 900's with 7.33 gr pellets. His spring are durable.

Ive read a heavier piston will help launch heavier pellets better.

[barcabarca]

thanks all,

I am really interested now that you have brought up all of this excellent information.  Maybe, I will install a spring kit and a new hector piston and shoot much heavier pellets..

that would probably run somewhere around 225 when all is said and done with shipping. about the same cost as a new d34!  but in the end I might have an air rifle in one of my favorite platforms that shoots around 22,23 FPE smoothly and carries that energy downrange because of larger pellets wt.

I wonder why they don't just build this version of the air rifle to begin with... Anyways, thanks to all...

[cliffspot]

I have put JM kits in about 5 guns. The critical component is piston seal fitting. Do it right and the power level should remain stable for a long time. Like my friend Orlando told me once......"If you fit the seal too tight, it will break in....take you about a million shots!" The JM seal is made of tough stuff, take your time fitting it and you will be fine. And don't go crazy on the Tar. I overdid it on my R7, then redid it and gained 20 fps. I have swapped out my JM kit in my R1 in 22 cal. Getting a true 800 fps with FTS pellets. Will see how long it holds. Have about 200 shots thru it so far. Oh...the glue on buttons JM sells work great too. Takes out the slop in the piston to comp tube fit....anything for consistency. All my JM guns have a extreme spread of about 10 fps MAX! Wish I could get that with my handloads!