GTA
General Discussion To Gateway To Airguns => The Shop => : tjk June 14, 2009, 12:04:06 AM
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Just thought I'd toss this question out. My beloved Sierra-Pro has always been one of my go to guns, and a great hunting tool in the field. Lately, I've noticed that there's been a slight bit of buzz and the velocity has dropped off. Now I've probably put aboutclose to 10k rounds through her since I got it back from the Tuna, so my question is,...Can a Macarri spring weaken over an extended period of time?? I don't think it's broken, but just seems to lack the punch it had before. For the most part, this rifle has been shot using Beeman Cro-Mags. Yesterday I shot some FTS's (shooting around the low to mid 700's)in it and noticed a slight bit of dieselling, but that cleared up in no time,....perhaps the seal may be worn out. Like I said, I've used this rifle ALOT, and thought I'd ask for some ops before I go tearing into it,...which I care not to do too often anyways. Tuning a fresh and raw springer is alot of fun,...but I hope to do the least bit of maintenance on my tuned rifle as I can get away with. Simply replaceing the spring would be ideal,...but if needed, I'd replace the seal as well. Just hate to "fix" what ain't broken!!!! LOL's tjk
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I am assuming this is a Siera Pro .22 Thomas
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No it's .177 cal. But like I said, it's seen alot of use!!! LOL's Got (or had) a freezer full of BT's from last seasons hunts. For a cheapo rifle, I'd have to say it's been one of the most consistant .177 shooters I've had. I wish they did make it in .22, but even then I wouldn't shoot the .22 Cro-Mags through it. The weigh "Leap" between the .177 and .22 cals of these pellets is way to much for a standard springer (what I call a rifle that's 1000 fps rated). I'm hesitant about shooting any of these monsters in my B-28 as well!! Thomas
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You got your moneys worth out of that spring if you got 10K rounds on it. Most factory springs would be lucky to get a 1/4 of that. To answer your question, I'd say yes, any spring, JM's included, can and will weaken with (in your case extended) use and time. I'd change the spring and the seal(it's got 10K on it too) and see where your at.
Regards
Nathan
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LLH, Yeah Nathan you're probably right!!! I just hate the thought of messing with a rifle that's been such an excellent shooter! Alas,.I guess the inevitable has arrived. Now Bob installed an Apex seal (I think?!?!), so I'm thinking of trying out maybe a Gamo Tesla seal, or the other Tesla seal JM sells. At the time he tuned it, he mentionned something about some scratching in the reciever,...but by now, maybe that has smoothed oout enough to opt for a different seal. I have got my moneys worth on this shooter!!!! I'll probably order the same spring (Tarantulla) since that's what he spun the guide to fit. Got the oils,...and may even button the piston while it's apart. Time to order up to Mr Maccarri!!!!tjk
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Tjk....as you know I had and still have a Sierra Pro that was very unpredictable. Shots were all over the clock....and very hold sensitive. Finally the origninal spring broke after over 3000+ shots. Near the end....I guess when the spring was becoming very weak or near breaking the shots actually settled down.
Put in another Crosman spring and gave her a simple home tune (More like a cleaning, heary tar and moly lube and smoothed down some sharp edges)...but the gun was still not accurate and hold sensitive. Got rid of the cheap Gamo scope and had a Bushnell Banner on her...and the accuracy improved immensely....but still abit hold sensitive. So I left the gun cocked (Spring compressed) for 10 hrs.....two times....to settle it abit. Now the SP shoots fantastic and accurate. I even took the scope off her and use her for the Open Sights Rifle match....and getting pretty good results for my level of shooting.
As for your Maccarri spring.....I'm definately sure that spring is more superior to any factory spring....but after 10,000 shots even it will get fatiqued....maybe for a change. If/when you're at it....give the seal a look-see to see if there's any serious wear....and change if necessary. Me also....I don't like to open up an airgun if not necessary. Good luck with your SP.
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Thanks for the encouragement Stan!! Yes the SP has been a faithful shooter for me, and I had the same initial accuracy problems you've experienced,....even after the turbo-tune!!!! But once you learn how to hold it as well as shoot it,...they are a dream to shoot. They can be persnickatey on how they're held!!!!Other than that it's simply point, aim, and fire away!!!! LOL's Luckily I still have the factory spring from my G1,...and if worse comes to worse,...I may just throw it in till I can get up an order to ARH. I'll have to stick with the glass though,...never had much luck with the cheap plastic "irons" it came with. For the money I've invested in it, I am well pleased and think I've gotten my money's worth for sure, so throwing another $30 or so for some new components is a no brainer. Besides, I want my 'hot-rod' ready for this seasons hunt. Thomas
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I can't comment on the "Iron sights" actually fiber optics yet. I've only used them to sight-in at 25 yards once (Took less than 15 shots) and did two 25 Yard Open Sights Rifle matches.....for a total of less than 75 shots using" irons". But I doubt the cheapo rear sights will hold up if I keep on turning their knobs. If/when it breaks I'll order one....a Weaver I believe and put it on the dovetail rails.