RWS 34 and 10.5 grain Crosman domed

[Ike the GSD]

I mentioned I installed a 33 coil mainspring in my model 34 yesterday and did a few chronograph tests before the batteries croaked. Well this morning I bought a tin of the 10.5 Crosman domed pellets just to see how accurate they were and to do a cursory penetration test.  The new spring appears to have increased the power of the rifle by 1.3-1.8 ft lbs I'll post exact numbers when I get new batteries in the chronograph. In the mean time I'd like to share some penetration results using this pellet. All shooting was done at 30 yards, .530" penetration into pine board and almost full penetration of two water filled gallon milk jugs. I was really impressed, my .22 R9 can only accomplish this with the Barracuda pellets although the copper plated FTT pellets come close leaving a dent in the back of the second jug. Accuracy is good but not the best, more than adequate for hunting though, at 10 meters 5 shots make about a 3/8"-7/16" hole. The new spring has made the rifle slightly more difficult to cock, but still very managable and the rifle has a very consistant and quick shot cycle. I'm thinking this rifle using these pellets will shoot completely through the body of a squirrel at least out to 30 yards.   Below is a picture of the second milk jug with the pellet sticking out the back side>>>

[Mark 611]

Interesting, what kind of numbers were you getting with the 10.5gn pellets?

[Ike the GSD]

Interesting, what kind of numbers were you getting with the 10.5gn pellets?

I think the only number you understand is 420 🔥🤣

[Mark 611]

LOL!!! that's funny no 420 in my world I got to keep a job!!!! 

[Ike the GSD]

LOL!!! that's funny no 420 in my world I got to keep a job!!!! 

I hope you know I was just joking LOL!🤣👍!

[Mark 611]

Were all good brother! I can take a joke

[Ike the GSD]

Well the velocity readings with these pellets are much lower than I was expecting, after the new seal they were averaging 703-707 fps, but the pellets must have an incredible B.C. because last night after the new seal was installed they shot completely through two milk jugs full of water at 30 yards whereas before they got stuck in the far side of the second jug! I know one thing I'm worn out trying to hotrod this 34 and I might just accept defeat and be happy with what I have.  As it stands I think I can expect pass throughs on squirrels every time up to 30 yards. When these pellets hit the 2 3/4" steel lolly pop targets at 30 yards the steel just rings, most of the time the pellets just make a splat sound...these things hit hard!! One thing I forgot to mention is I gave the barrel a really good cleaning, there was a tremendous build up of black residue ( I mean black as coal). I first used a bronze brush on a pull through cord followed by a little JB bore paste and several patches followed by two 91% isopropyl alcohol soaked patches and a few more try patches to remove the alcohol thoroughly.  Finally, I ran a patch lightly coated with CleaNbore bore condidtioner followed by two dry patches. Well that's about it guys 👍

[Nukall856]

I have used the CPUM 10.5 in a lot of different air rifles in Multipump, PCP and Break barrel. In most break barrels either Spring or Gas piston the CPUM 10.5 gr usually create around 1 FPE less than 7.9-8.7gr. Also CPUM 10.5gr have a wide head and usually fit a bit too snug in most barrels. I have a F4 TG-1 that I use the CPUM with for now and get around 785FPS and around 20 FPS Spread. I'm thinking to switch to SigSauer Dagger 10.0gr these have a  lighter fit than the CPUM.
 The CPUM can do good in some Multipump Airguns- usually if the light pellets don't work I check if CPUM will fit and fly. Usually good power if the fit is right.
 My Beeman 1022 sends the CPUM around 620 fps also with a 20 FPS spread.
 Have used them in 1377s, DP880s, and a couple Gas and Springs Piston that can shoot them good.
 They good but not the best unless you have a loose leade barrel.

NVak

[Ike the GSD]

I have used the CPUM 10.5 in a lot of different air rifles in Multipump, PCP and Break barrel. In most break barrels either Spring or Gas piston the CPUM 10.5 gr usually create around 1 FPE less than 7.9-8.7gr. Also CPUM 10.5gr have a wide head and usually fit a bit too snug in most barrels. I have a F4 TG-1 that I use the CPUM with for now and get around 785FPS and around 20 FPS Spread. I'm thinking to switch to SigSauer Dagger 10.0gr these have a  lighter fit than the CPUM.
 The CPUM can do good in some Multipump Airguns- usually if the light pellets don't work I check if CPUM will fit and fly. Usually good power if the fit is right.
 My Beeman 1022 sends the CPUM around 620 fps also with a 20 FPS spread.
 Have used them in 1377s, DP880s, and a couple Gas and Springs Piston that can shoot them good.
 They good but not the best unless you have a loose leade barrel.

NVak

The choke on this rifle seems really tight starting about 5" before the muzzle, I wonder if that might be slowing things down? I've added a 33 coil Vortek mainspring and a new Vortek piston seal and I still can't get above 12.5-12 3/4 ft lbs? The only thing left I can think of is to add a thick washer in front of the top of the mainspring to add a little weight to the piston? I see people claiming 14+ ft lbs with this same rifle same .177 caliber and I don't see how they're doing it?

[Nukall856]

Ike the GSD,

   If you try HNFTT 8.7gr in 4.52mm they may fit good and not snug like the CPUM and you most likely will pick up <1.0+FPE.
 With my TG-1 Vantage, same action as a Optimus, I get 852FPS and 14 FPE. With the CPUM it get around 13+/-FPE. CPUM May be a bit Snug for your barrel and my TG1 so a loss in power is expected.. enough shooting..;  CPUM fit in my F4 is good to lightly snug, so does good enough.
 I have a UX Airhawk <yet to Chronorun> but from reading it has a shorter piston stroke than the M34, does very good with 7.9-8.4gr and has a good tight leade for light fit pellets < EHD 7.9gr, SSM 8.2gr, BHT 8.2gr, RSD 8.3gr, PRN 8.4gr > I'm sure other light fit pellets like Excite Spikes 8.7gr would do very good.
 Ok in Spring piston Air rifles, pellet fit is the most important for power, finding a pellet that fits good and has a consistent shape yeilding lower fps spread,,, so on so forth XD
 If you want low costing pellets try the CPHP 7.9gr, the fit varies abitand is not Soo snug like the CPUM and you might gain 1.+ FPE along with a good enough 20FPS spread. Usually where CPUM is too snug CPHP does the job good enough to 30 +yards.
 I have a RWS M34 Classic and get 17.8FPE with 14.7gr Excite Hammers.. different story but same Air rifle in .22
Ok edited 7 times, abit Squirrelly but yahm saying
Excellent Work Stay Alert

NVak