My New Marauder

[dcmaruader09]

I just got my new .22 cal Marauder Friday this week. Took pictures that I wanted to post here but it looks like I am not allowed to post as I cannot find any links to attach files or past pictures--perhaps it was just me and I cannot find the right link. In any case I will just describe my initial observation using descriptive words:

I got mine from PA, and it was well packed and survive the rough handling from UPS. It came with the Benjamin hand pump, 3 .22 cal extra clips and crosman premier hollow points and 4X16-40 scope. The serial number was a little bit strange, 809 and the number 4 at the end stamped on the air tube assembly. I think 809 stands for made in August 2009. I checked brown carton from Crosman and I found a sticker stating 8/5/09, not sure if this was the manufacture or shipping date.

Out of the box the stock looks good, no scratches or rough finishing, however, not as well finished as the other more expensive over $1,000+ European airguns. More scrutiny and closer inspection revealed what looks like a stripped head slot on the Plunger Assembly, Item 7 (Part# 1763-106) on the marauder parts lists. It looks like someone at the factory over torqued the plunger bolt/set screw and the slot where the screw drive sets was almost completely stripped. Third item I notice was the O-RING, AS568B-118 (part#1763-026) on the Fill Adaptor Assembly, was over tightened to the point that that half of the o-ring was deformed and torn with small pieces of rubber. I remove the barrel band assembly as some folks are saying that this can cause the barrel alignment issues due to UPS handling, and sure enough, it was misaligned. Took my allen wrench and loosened the band and all is well, I can see light around the shrouded barrel when held against light. Lastly, I open the barrel shroud assembly to check and see the four shrouds and it looks well made and no issues there.

OK so overall apart from the issues I identified from the preceding, I decided to start pumping air into the MROD's air tube. I was initially worried about the condition of the o-ring as it may not hold, or worse, start leaking HP air. 160 strokes laster and lots of sweat, I got her to 2000PSI and I decided to dry fire to test and see how seriously "quiet" this AR really is. Well, I was extremely pleased from what I heard--just like the reviews I've seem and watched on youtube, the AR is really and unequivocally the "QUIETEST" production PCP on the market today! I say production, as other PCPs can be as quiet or even quieter that the MROD, but that is after you have spend additional $$$ for after market shrouds. It is not dead silent, but man, this is quieter than my subsonic .22 cal rimfire ammo as 500FPS...WOW I am impressed. I then proceeded to load the pellet rounds onto the 10 shot repeater clip, pulled back the bolt, inserted the clip and push the bolt forward...the bold will not engage forward no matter how hard I was pushing and after several attempts, I broke out the manual and there it says on page 3B
"With the cover of the clip facing the butt of the air rifle insert the clip from the right side and push it inward until it snaps" What I was neglecting to do was "push the clip inward until it "SNAPS"... doh...LOL... the clip has to snap before any pellet can be inserted into the breech...wheew...

I aimed the MROD to my target, squeeze the nice and crispy trigger and there goes my first shot...again, another wow moment...as the pellet came flying out the barrel and into the target. Cocked the gun again and the 10 shot repeater is really nice for the first time, I do not have to reach for a pellet to load, I just continue to shot away being careful not to double load as others I have heard had done inadvertently. So overall I have no issues with the Marauder, I just need to call Crosman next week about those "nit picky" issues about their QA. I wonder if any of you have seem these same quality issues with your marauder.

Now I have some question for you folks that have had your MROD for a while now about the the fill pressure and factory settings. I have not change any of the hammer preload, striker, and metering--they are all factory default at this time. My question to you is, what are the factory settings for hammer, striker, and metering? Second question is, I pressured my MROD to about 2800 PSI and test fired a few rounds and I seem to like this setting since I can get a lot of shots in between fills to about, say 1600 PSI before the next refill. Are there any issues with this higher fill and leaving the factory settings/defaults to the original values?

Sorry for the long post, but this Marauder is a keeper after I have tested and evaluated other comparable PCPs and break barrel, this is the best thus far.

- DC

[huffelfingre]

Great post !!!!!!!
Thank you

[unirdna]

For my gun, the factory settings fired a nice string of 14.x pellets from 2500 to 1800 PSI. Above that pressue my gun exerienced some valve lock. Below 1800PSI my hammer started to bounce a little, and the pellet speed dropped off.

If you want to shoot heavy pellets, like kodiaks, you may want more "oomph". My gun is currently set with the metoring screw completely out (4.5 turns - you can go further, but it won't make a difference), and the striker and springer are both completely out - minus one full turn (in). Mind you, this setting uses a lot of air compared to the factory setting. I only get 20 shots - from 2800PSI to 2200PSI until I refill. But, those 20 shots are at 845-860fps with a 21.1g pellet. Translating into 34 fpe! I can get 35 shots above 800fps (3000 PSI-1900 PSI), and if I was out hunting, that's what I would do. But, if I'm near an airsource, I just fill it up every 2 clips in order to keep my accuracy more consistent.

When I had the gun tuned to shoot 14.3g pellets at 830-850fps, I could get 30-40 shot strings with 30fps variation. I think my setting for that one was - metoring screw 2.5 turns out. Spring at max - minus 2 turns. Striker at max - minus 4 turns.

[dcmaruader09]

Mine is still at factory settings and I have been running the pressure to about 2900 to 3000 PSI. It also has been firing a nice consistent "dime" groups of 10 shots from approximately 25 yards. I am currently using Crosman premier hollow points 14.7G. I can get up to 80 good shots before the PSI drops to 1900-1800 and then it goes south, and I think I am getting these tight groups because these pellets are very "compatible" with the Marauder. I have not tried any of the heavier Kodiaks as of yet...just too busy leaning the features of this PCP.

You mentioned "valve lock" and I am not sure if I have experienced this condition yet. Can you elaborate? Would you know at what FPS are the standard factory settings? It would really be nice get a chrono to fine tune this AR. However, my budget for now is only good for a Scuba tank refill station. I got the Ben pump and it is a total work out to 3000 and I am not certain if the pump will be a keeper--as the Hill pump will be a better option.

[unirdna]

Valve lock:

To understand the term, you need to know how the gun works. When you pull the trigger, the hammer strikes the air valve. The momentum force of the hammer opens the valve, allowing air to escape for a moment (this is the air that powers the pellet). The pressure inside the air reservoir pushes back on the hammer, closing the valve. Hammer strength, of course, is controlled by both the tension on the hammer spring, and the distance the striker setting is set. The amount of air that escapes is controlled first by the setting on the metoring screw (out more = larger "hole" for air to escape), and secondarily by the force at which the hammer strikes the valve.

Valve lock is the condition when the internal pressure is too high for the hammer setting to properly open the valve. What you get is a sub-standard velocity because it simply didn't get a big enough blast of air. If you want to fill the rifle to higher pressure, you need to increase the hammer strength to compensate for the increased pressure.

This begs the question: why wouldn't you simply set the hammer to max - then you wouldn't have to worry about valve lock. Well, there is a good reason not to do this. On the flip side of the coin to valve lock is [what I refer to as] "hammer bounce". If the internal pressure of the reservoir isn't high enough to "shove back" the hammer, the hammer will "bounce" on the reservoir valve. This creates a sort of pft, pft, pft, pft sound. You'll surely notice this. If this happens, you're pellet velocity is certainly slow, and you are wasting a lot of air with the extra puffs.

The goal is to have all these opposing forces balanced out. When you do, you should experience a shot string that has a velocity "bell curve". You'll have a tiny bit of valve lock, then the pressure will allow for a full blast, then the internal pressure will drop and your shot string will eventually decay (velocity). Your goal, as the tuner, is to adjust these settings (metoring screw, spring tension, and striker distance) for an optimal shot string. You want two things - as many shots as possible, and as close to the same fps (velocity) as possible.

It goes without saying that you can achieve longer shot strings when tuning for lower velocities or lighter pellets.

Hope that was helpful.

[unirdna]

I got the Ben pump and it is a total work out to 3000 and I am not certain if the pump will be a keeper--as the Hill pump will be a better option.

No doubt, the pump takes some force. I've found that it's best to lock my arms and drop my weight on it. Doing this, I can last considerably longer than simply trying to "muscle" it.

[dcmaruader09]

Valve lock:

Your goal, as the tuner, is to adjust these settings (metoring screw, spring tension, and striker distance) for an optimal shot string. You want two things - as many shots as possible, and as close to the same fps (velocity) as possible.

It goes without saying that you can achieve longer shot strings when tuning for lower velocities or lighter pellets.

Hope that was helpful.

+1! Well said, it really helped. Thanks for expounding on the my valve lock question. I am a newbie here and I am amazed about all the aspects of the AirGun world.

My challenge now is how to "achieve as many shoots as possible--and as close to the same FPS"--just like you said. I take it that if I was using the CPHP as my baseline, then I switched to the heavier Kodiaks, it would a new calibration settings of the Hammer, Striker, & Metering.

I wonder what settings and pellet grain on a .22 cal Marauder being advertised to go as fast as 1000 FPS? (Hammer, Striker, Metering, & PSI)