UNDERSIZED JM R1 PISTON SEAL AND OVERSIZED JM R1 REAR GUIDE;

Well, the Maccari piston seal was undersized. Nice seal. Harder material than the soft nylon, parachute HW factory piston seals, but at least in this R1, definitely undersized. Without the spring in the R1, the Maccari sealed piston all but moved with simple tilting the compression tube up and down. Gravity enough to move the piston. Oops. Better go back to the factory R1 piston seal.

Another problem. When I had installed the Maccari 13 ft/lb tune kit, the base of the rear guide was a real tight fit, but as I was using the spring compressor, I did not realize how tight a fit. Well, it was so tight a fit, that even as I unscrewed the R1’s end block, the 13 ft/lb spring lacked the power to push the end of the rear spring guide out of the R1 compression tube. What I should have done would have been to try to insert the tune kit into the R1 compression tube backwards. That is, rear guide base first. That would have detected the over-sized rear guide base.

Heroic measures finally dislodged the JM 13 spring guide out of the R1 compression tube by partly unscrewing the end cap and then violently and strongly (with the trigger block out of the gun), slamming the piston against the base of the rear guide in a repeated hammering action. Eventually, I was able to hammer the JM tune kit rearwards enough that I then could take a large, rectangular cross section gunsmith screwdriver and jam it into the rear guide hole the piston stem passes through, put a wrench on the screwdriver shaft, and with a lot of effort, screw the JM rear guide out the threaded end of the R1 compression tube.

Amazingly, the R1’s barrel was not bent and the R1 cocking shoe was not damaged beyond use. More amazing was that I didn’t break the JM rear guide.

Another point of interest in the Maccari R1 rear guide was that it was so tight on the spring, that upon firing, the spring was unable to fully expand. The coils still on the rear guide were noticeably still partly compressed while on the forward portion of the 13 ft/lb spring, the coils were fully expanded. Talk about a tune kit that was made tight enough to need a “wear in” period. No spring twang was going to happen due to loose guides on this baby!

Lucky me, I had a spare R1 factory piston seal and could dump the JM piston seal and install a factory seal. How did that affect chronograph performance?

WVED (ED CANOLES) GUIDES:

Well, first things first. I had a spare JM 13 ft/lb spring and just for fun, sent the mis-fitting JM 13 ft/lb tune kit and a spare JM 13 ft/lb spring to WVED (Ed Canoles the custom piston crafter). Ed makes his own guides, though is more of a Beeman R9 guy than a R1 guy. But I hoped he could lathe the Maccari rear guide down to size and also, due to his precision work and reasonable prices, make me a guide set for the spare 13 ft/lb spring while he was at it.

Which, WVED did. He turned the job around and the mailman delivered a box from
WVED within a couple weeks of my original mailing.

WVED was not able to remove the JM spring off the JM rear guide, so he was not able to lathe down the JM rear guide. I did it later the clumsy and less precise way holding the JM tune kit in one hand and a file in the other and filing away on the O.D. of the rear guide base, while slowly turning the kit. In about an hour, I had the JM kit where it would fit snug and still be removable.

But the delrin/steel base WVED guide set was so pretty, precise and of “can’t pull the spring off but coils expand fully on shooting” tight, that I wanted to try WVED’s work first. The filed down JM kit could wait for later.

I put the R1 back together, factory piston with the factory parachute piston seal on it with a little Beeman moly grease on the sides, and after some warm up shooting, chronied I the R1 with the 13 ft/lb kit again.

13 FT/LBS ME WITH THE 13 FT/LB ME MACCARI SPRING AND WVED GUIDES:

With the JM 13 ft/lb ME spring and its WVED guides, instantly, I was getting about 875 fps with 7.9 gr cplites, which was about what one should expect out of the kit, that is about 13.4 ft/lbs M.E.

Ok, all was well. Firing was still crisp but more sedate. Cocking effort was more like my Beeman R9 now. My R9 having similar power, so that made sense.

R1 LESS HOLD SENSITIVE AT 13 FT/LBS:

At the range, the 13 ft/lb JM/WVED kitted R1 was pleasant to shoot and for sure, easier to cock. Groups were reasonable, both with 7.9 gr cplites and 8.4 gr JSB Exact 4.52 domes. For instance, despite about a 15 mph cross wind, the 13 ft/lb R1 put five JSB Exacts into a 1.0” ctc group at 60 yds with using a 2 pt sitting with rest hold.

But the wind was blowing too much to allow creation of a trajectory plot chart that I could have confidence in. So the R1 awaits a calm air, 5 to 80 yd trajectory plotting session at the range. But there is hope. Time will tell more if I finally had a good hunter in my Beeman R1.


BACK TO THE HUNT:

Having arrived before the ground squirrels emerged this hunt morning, I took some time to test the 13 ft/lb R1 for hold sensitivity. The air this early in the morning was almost dead calm. So I set out a cardboard box with three one inch black ink marker-drawn bulls on it, at a Bushnell laser rangefinder-measured 60 yds. I shot sitting in my inexpensive aluminum Costco, folding camp chair. The one with padded arm rests.

I shot three ten pellet groups at 60 yds. One group was 3 pt sitting rested; one was 2 pt sitting rested; and one was 2 pt standing rested. At 60 yds, the 2 pt sitting and 2 pt standing had the same poi. The 3 pt sitting rested group poi was about 2/3” lower.

9:30AM and it was time to stop the target session. The sun was out. The overcast was breaking up and using my Bushnell 6x25mm Custom Compact binoculars, I could see a few ground squirrels dotting the rain-greened, flat lands of the fenced cattle pastures. Not many, but enough to be worth a try for.

The R1 went back into the cheap, black plastic hard case and back into the car. I was getting a late start anyway and these late in the year days are short. No time to experiment nor play.

So out came the .177 AirArms TX200 Mk3. A very good springer for ground squirrel hunting. Hold insensitive. It cocks without tiring me, is accurate, and a short, handy yet heavy and stable springer. Pre-hunt, right after a fresh barrel clean (cplites being a bore-fouling pellet), it chronied 7.9 gr cplites at 905 fps. Later, post hunt the same day, that evening, I got 880 fps. It had a Maccari TX200 tune kit installed approx. 500 pells ago. Still settling in? Or was it the difference between a dirty bore and a clean with a light oil coated bore?

Regardless, I like my TX200’s also because CHAIRGUN, the computer generated trajectory plotting software matches my real life, actual shooting session trajectory plots. Wish I could say the same for my Weihrauch/Beeman break barrel springers though.

ALL DAY IN THE SAME 20 ACRES:

The cattle pastures I spent the entire, short December day hunting, were only an estimated 20 acres. The big, adult California ground squirrels were thinly scattered, but there were enough to keep me busy. All day. Especially so because the weather conditions changed.

CURSED BY WIND:

I had thought I would have all day with calm or low winds. While summers tend to be calm mornings and windy afternoons, winter days here are often enough calm or low winds only, all day. Not today.

The hunt started out with my cherished dead calm wind. So calm that after my morning Beeman R1 target session and before I put it away, I even took one shot with the R1 at a starling mixed in with a hundred or so blackbirds, the starling sitting on top a tall, wood, power line post. Distance was about 35 yards.

At the R1’s shot, the starling flew off, angling down, hanging a leg. It would have been more of a slam dunk shot with my Beeman R7. I was more practiced with the R7. Goes to show that 6.5 ft/lbs with a precise trajectory plot chart beats 13 ft/lb R1’s without. Definitely the R1 needed more range time and more work on a trajectory plot.

With the TX200, I hunted in a leisurely walkabout manner up and down the cattle pastures, covering about 1/3 mile up and then hunting back again. I spent most of my time in the middle of the pasture flatlands where a small rise and est.15 foot high cut bank in the side of a low hill touching one part of the pasture, harbored a small squirrel colony of about 40 squirrels.

I shot with a 2 pt rest off the Samsonite adjustable camera stand rest, sometimes sitting, sometimes standing. Rains forecast but the ground still dry. The squirrels were kind of spooky. I found that after a few shots, they went down their holes and after about 30-40 minutes the colony squirrels still had not re-emerged. Someone had probably been firearm hunting them recently to spook them this much.

Not good.

The wind was my worst problem though. Squirrel spook distance was never beyond 70 yards and the TX200 was good to 70 yds. In calm air.

But I was not getting the calm air I needed for longer shots. The wind unexpectedly became strong and brisk out of the west and stayed about 20 mph all day. I saw maybe 90 squirrels total. I was only getting about one in three that I tried for. I had hoped to pretty much clear this pasture of most of its squirrels today.

I failed.

By 3:30PM, the hills to the west were casting shadows over the cattle pasture. The squirrels disappearance once the shadows shaded the pasture fields made today a shortened hunt. The day ended up with only 31 ground squirrels.

I got home early.

Better luck next time?

Robert Hamilton, California, along the Pacific Ocean coast
1 Dec 07