Page 1 of 1
Help Needed Daisy CO2 air rifle
Posted: Mon May 26, 2008 12:56 am
by chattron
Hello guys i have bought a Daisy 888 medallist CO2 air rifle.Its advertised max MV is 500fps at ME of 4.3ft lbs.I have been using about 9-10grain RWS wadcutter pellets but i get significant drop in velocity compared with Anschutz 2002 air rifle.I had installed the CO2 cylinder as mentioned in manual.It would be helpful if someone could analyze the problem and suggest some remedial measures.Bye.
Posted: Wed May 28, 2008 12:06 pm
by blades
Check your pellets for weight, most rifle match pellets are 8.2 gr, Pistol are 7.9gr. A 9-10 gr. pellet weight would give a much slower velocity. I would guess in the 10 to 15% area. I do not know what Daisy is using for their advertised velocity, but it might be 6.9gr or less which is not uncommon. Then there always is the sales departments embelishments to deal with also. Typicaly 470fps morphes into 500 in the sales office.
The one review I read did say 500fps, but there were no chrono results to back that up. So I would suspect just a repeat of the advertising copy. I never have had a Daisy that chronoed above 475 in stock configuration using match pellets of 8.2 gr weight.
The units shoot well for their price point and purpose.
Posted: Thu May 29, 2008 9:45 am
by jhmartin
1st .... I agree a 9-10 gr pellet is HEAVY
2nd.... is it a used rifle?
If so, if the previous owner kept it cocked with a CBI in it, the hammer spring may be slightly compressed.
Disassemble the action (carefully as springs can fly), and stretch the hammer spring out a few mm (4-5mm) ... it won't take very much.
Don't go too far as it won't make it shoot any faster and will be a real bugger to get back together.
If it is a brand new rifle, shoot it about 500-1000 times and then chrono it ... sometimes it takes the valve some time to work itself into constant velocities that are a bit higher than brand new. A 2-4mm stretch at this point seems to smooth out the velocities.
Also make sure your cylinder is not too full (my MAX tare weight is 475 grams) ... fill over that and you risk a blown burst disk and very inconsistent initial velocities until you get some of that CO2 bled off
Also remember that the 2002 is a $1500 rifle with an air regulator, and the 888 is a $250 rifle that uses CO2 vapor point as the regulator. I don't think you'll ever see the 888 shoot quite as fast as the 2002
Posted: Thu May 29, 2008 12:06 pm
by SRichieR
Our club 888's are typically between 450 to 550 fps. Two guns were just over 600 fps. Feinwerkbau's were all 600+ fps.
Pellets used were H&N from CMP and Vogel's.
Posted: Wed Jun 25, 2008 12:17 am
by chattron
Guys thanks for the tips.Got some more queries.Can the barrel of 888 be extended by adding some type of threaded extension etc?Also if this is not possible can a longer barrel be fitted say about 24inch in place of original.If this can be done then what type of replacement is advised.Awaiting your replies.Bye.
Posted: Wed Jun 25, 2008 10:47 am
by GaryN
I presume you are asking about extending the barrel in an effort to increase pellet velocity.
You do NOT want to extend the barrel with a threaded extension. The probability of perfect alignment of the stock barrel and the extension is so close to ZERO that it might as well be ZERO.
Replacing the barrel is a tricky thing. If the co2 that is released is just enough for the stock barrel, then by using a longer barrel you will simply slow the pellet down, opposite of what your original question was. A longer barrel will work ONLY if there is sufficient co2 released to keep pushing the pellet out the muzzle.
Posted: Wed Jun 25, 2008 2:21 pm
by jhmartin
As a followup to GaryN's response ...
What are you trying to accomplish by extending the barrel?
--a) Increased velocity? (totally agree with Gary's response)
--b) Longer sight radius? (slide the bbl weight fwd or make a sort of "bloop tube")
--c) More weight out in front? (Add another bbl weight)
If you are shooting within the 3-P Air Rifle council rules, you can only go so far on (b) & (c) .... not allowed with (a)