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Discussion Starter · #1 ·
I had some serious accuracy problems with my son's 17V last summer. My 50M groups hovered around 3/4 inches. In any gun but a bull barreled 17HMR these would be acceptable but I felt this needed some improvement. A recrowning , combined with a mild trigger lightening, seemed to do the trick. Groups were cut in half immediately. As time went on, they became smaller yet. The rifle now shoots 1.5" at 170 yards and that's allowing for wind demons that frequent on our desert range.

As with all 17's, there is a certain amount of break-in that took place, but the effect of the recrowning was instantaneous. If you have troublesome rifle you might want to consider spending the $$ on a recrowning. Can't hurt. ~Andrew
 

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Andrew, was there a noticeable defect at the crown? Or was just a expedient, relatively cheap, thing to just try out in case it worked?

I have an old Mossberg Plinkster that I really like. It used to shoot incredible groups until, due to a broken firing pin a second shot was fired after a dud, and got a ring in the barrel. Anyhow, I managed to find a new barrel fron Gun Parts Corp, and installed that. The new barrel has never shot as well as the original. I'm getting 1.2" 5-shot groups @50 yards and 1.75"-2.0" 5-shot groups [email protected] 100 yards. The original barrel I averaged .975" @ 100 yards, with a best group once (really!) of .4". That one was 5-shots at 97 yards as they were doing some work to the backstop and targets had to be set a bit closer that day.

I've looked at the barrel crown with all kinds of magnifiers and lights and don't see anything that looks off. Should I re-crown anyhow?

I'd like your opinion, please.

Luis
 

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Discussion Starter · #3 ·
luisyamaha: On my son's rifle the crown looked a little off-center. this was easy to detect as the existing crown was a recessed cut, 90 degrees from the centerline of the bore. The edges of this cut had been broken with s slight chamfer. This chamfer looked suspect and that steered me towards the crown. It was easily to accomplish for me as I did it myself.

As to your Plinkster, the crown on those is radiused, correct? These can be difficult to judge when it comes to concentricity. Having someone chuck it up to clean it off to, say, an eleven degree crown, would do no harm and might do some good. Barrels are finicky. What worked fine with regards to bedding and ammo from your old barrel might be needing readjustment for the new tube. Too bad that buldge wasn't at a point where the original barrel could have been recrowned to a short (but legal) length! I had a Mossy 44USA someone had cropped the barrel on to use as a silhouette rifle. It shot under 1" at 100 also, and occasionally dropped 5 rounds near the 1/2 inch mark so I believe you when you recount the Plinkster's accuracy.

As I mentioned. A recown will never hurt, but you might want to look at bedding and other mechanics before hand. Got a buddy with a lathe?? If so, just do it anyhow. Good luck! ~Andrew
 

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Thank-you for your prompt response, Andrew. You're right, the muzzle is radiused. And, yes, the bulge was about 6" back from the muzzle on a 20" barrel. I'm going to look around and see if the old barrel is still around. I have a small lathe, so maybe I can practice cutting and giving it that 11 degree crown with the old one.

As for the bedding etc., the rifle has a stud on the barrel a few inches in front of the receiver and that is its only attachment point. I have tried the two or three variations. 1) Card under the fore end to pre-load the barrel up. 2) Making sure the barrel wasn't touching anything from a couple of inches in front of this stud. 3) Actually putting a washer between the stud and the stock to sort of raise everything off the stock. Last time I used it was 10/2/03 and averaged 1.86" for 4, 5-shot groups @ 100 yards.
This with a Tasco 4-16X-50mm. Numbers 1 & 3 above did worse.

I'll try and, weather permitting, go to the range tomorrow with all three of my .22 rifles to try out 4 different brands of ammo and establish a base line with the Mossberg again.

Thanks again!
 

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Bad news on the Mossberg. Did go shooting 11/19/04. The following are the resuts of the different ammo in both the Mossberg 377 Plinkster equipped with a Tasco world Class 4-16X-50mm scope and a Clark Custom 10/22 equipped with a Bushnell 4200 4-16X-50mm scope.
Groups are averages of four (4) five-shot groups at 50 METERS. Five shots were fired with each ammo type at a sighter target to check they would at least be within the 4" targets I was using.

Mossberg Clark

Blazer 1.48" 0.84"
Sellier & Bellot Club 1.54" 0.62"
RWS 1.69" 0.63"
Federal Gold Medal Target 1.74" 0.91"
CCI Velocitor 2.06" 1.27"
Federal Lightning 2.11" 0.75"

Locally S&B was cheap ($1.80/50), RWS was expensive, ($6.00/50), Blazer was cheap also. Federal Target was (2.00/50). Federal Lightning and CCI velocitor were $2.95 and 3.95 respectively for a box of 50.

Most consistent (least difference between largest and smallest group) was the RWS, followed by S&B. The smallest group went to RWS with 0.46".
Second smallest group went to S&B with 0.48".

Unfortunately I was out, and couldn't get Winchester T-22, which is my usual load. Average for T-22 on the clark, on another day was 0.80".

Soooo, S&B gets the nod, same as T-22, and Blazer 9even if it doesn't work with my 1897T's light hammer blow). RWS and Federal Target the scope had to be adjusted UP 8-10 clicks compared to the other loads. The CCI required adjustment DOWN 12 clicks. All others hit close to POA.

Darn! Now I'll just have to play with that Mossberg!

My results, my rifles. On 11/19/04. Yours may vary.
 

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Where did my nice columns go? :( The first number after the name of the ammo is with the Mossberg and the second with the Clark. 8)

Really, I had it all lined up when submitted! :oops:
 

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Discussion Starter · #7 ·
Luisyamaha: I'd figured it out, no problem. In looking at your results I am reminded of a JW-15 rifle that's sitting in the corner of my office. I love these chinese copies of the Brno#1 sporter. I have several right now and owned some of the first of these guns that came into the country back in the early eighties. Their crowning achievment -besides being stout and inexpensive- is that they generally shoot really well. I used to build "budget" silhouette rifles out of them and never got a complaint about accuracy. Then there's this one. It will shoot one bloody hole at 25M with PMC "ZAPPER" but nothing else. I even tried Aguila SE Hi Velocity which is (ahem!) quite similar to the PMC offering. No go. Until I change something -the bedding or the crown, both of which seem fine- this rifle is a ONE cartridge rifle. Maybe you have the same problem and just haven't hit on the right recipe yet.

Just for yucks, you could take a loaded round and and see how far the bullet goes into the rifling when you insert it nose-first into the bore. That might be a good indicator of rifling wear. If it goes in past the shoulder of the bullet, think about a re-crown. Good luck, Amigo. ~Andrew
 

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Andrew, sometime ago Guns and Ammo mag did a report/test on .22lr ammo of many sorts and brands. They'd found the Zapper to be the surpriser of the bunch. They said it was accurate enough to be put up against any of the "target" stuff depending on rifle used. They didnt say it was better but for the price is the most accurate.

I dont like Zappers because they really shoot dirty in my auto but would probably be a round of choice in a bolt.


Hey guys, how much for the re-crown?? Just a ballpark figure??


Perferator
 

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Andrew: I'll understand you to mean to stick a loaded round on the muzzle end of the bore. I did, and no, the shoulder doesn't even go in at all. I'm sure if I pushed real hard it would, but I think that's not what you wanted. The other, narrower part of the bullet went in real easy.
I never did find that old barrel. So I'll have to try it with the real thing. How much do you suggest I cut off? Should I just face off the end of the muzzle straight and then re-crown? Or should I cut off 1/2" or 1" and then re-crown? The barrel is 20", so I should be able to cut some off if required.
 

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Discussion Starter · #10 ·
Luisyamaha: If you have a lathe then you're free to go back for seconds. I'd start with 1/4" and cut an 11-degree crown. See if it helps. Remember to use a very sharp tool and cut from the bore outward on your final cut. Good luck! ~Andrew

Perferator: Some gunsmiths are pretty good about crowning, some act like it's brain surgery. Cost often depends on the set-up time. Having the rifle dismantled to it's barest components -just the barrel and reciever- often lowers the cost.

Yeah! I know that the PMC Zapper is accurate... just hard to get in my locale. I never mind dirty ammo but I'm more of a bolt gun guy. That Aguila "SE" Hi Velocity is really good in all of my guns. I liked it so much I bought three bricks of the same Lot# just to make sure! ~Andrew
 

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Well, the deed is done. Upon close examination, I noticed some imperfections on the rifling about 3/4" in from the muzzle. So I practiced cutting and making the 11 degree cut a couple of times and then cut off at the 1" mark with a hacksaw. still have 19" of barrel. Cut at 90 degree and then at 11 degree fine cut. Touched up with black magic marker for the time being.

Will let you know what happens next time at the range.
 

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Went to the range yesterday. :lol: Due to time constraints didn't shoot as many brands as the first time, but instead tried out the two best performers the from my base line. 8) With four 5-shot groups at 50 meters the Blazer improved from 1.48" on 11/18/04 to 1.10" on 12/02/04. Thats a 25% improvement. The Sellier&Bellot went from 1.54" 0n 11/18/04 to 1.23" on 12/02/04. A 20% improvement. This looks promising! :D I know the shooting conditions we not as good yesterday as on the previous time, but I wanted to get a "feel" if there had been an improvement. 8) Next chance I get I'll try out all six loads again.

Will keep you informed of my adventures with the "Plinkster".

BTW, for those of you who've only heard of the "new" Plinkster, which I've heard of people bad-mouthing, :shock: mine is the old, old "Plinkster". This one is a butt-fed (15 rounds LR), plastic thumbhole stock, no fixed-sights, style. It is attached to the stock by a single screw, to a stud dovetailed into the barrel. It was only the second rifle I ever bought (used) and for a long time it was my most accurate rifle, so I'm very attached to it, even if its glory days seem to be over. 8)
 

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Thank-you Sure-shot for the info. On this particular rifle it is very easy to put in the lathe. Just remove action from the stock, (one screw) and remove the scope from the action (two screws). Stick it through the tailstock. So it's easy enough to do. What I'm reconsidering is the 11 degree target crown. If the bore is not concentric with the outside of the barrel an angled crown results in a not square end of the bore. A recessed 90 degree crown does not have that problem. If it is concentric one should be as good as the other. I'll be doing more playing around with the rifle before making any other changes. Keeps me out of trouble!

Off in the Yamaha for the ESR. (Early Sunday Ride :lol: )

Luis
 

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I wonder if this is why I can't get my 190 Win to group. It has what looks like an impact mark on the outside edge of the bevelled crown- it almost looks as if it were dropped/abraded against concrete. The inside of the bevel and the edge of the rifling look fine... comments anyone?

Regards,

Doc Sharptail
 

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Discussion Starter · #18 ·
Doc; That's why the crowns are beveled and recessed: To take the abuse that otherwise would hit the rifling lands. I have a few rifles with "external" dings and they shoot fine. In the 190's case, it may be that it was cleaned from the muzzle too often and in which case, a recowning would be good.

I had two junker 190's I pulled the barrels from to make .22 liners. All of the guns I relined with these homemade liners shot well, despite the fact that the original rifles weren't that accurate. I think there's something in the mechanics of the 190 that might inhibit accuracy. I've always suspected that the pin-strike was too light or too easily dampened by grime. Just a thought. ~Andrew
 

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What bugs me is this rifle is a performer when it comes to function- it feeds and fires and cycles everything I put into it without a hitch. I can shoot subsonic ammo in it that usually stovepipes in my 10-22 with no problems at all to cycle....

How do you feel about using a lr. chambering reamer to re-crown? I am pretty sure I can get my hands on one....

Regards,

Doc Sharptail
 

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Perferator said:
Hey guys, how much for the re-crown?? Just a ballpark figure??
I had an old military surplus rifle recrowned last year. My gunsmith only charged $15.
 
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