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Discussion Starter #1
Went & got myself a new deer rifle. Saw what dmsbandit did, & after much research, decided to try it out myself. Only I got the stainless. After breaking in the barrel, I started trying different loads, as well as some ammo I had. Most of my groups are 2.5" or worse. I tried Nosler 165 BT, Hornady 150 SP, Berger VLD 168. The one factory ammo that shot pretty well was Fed GM 175, about 1.25" group. I know it's hard to advise w/out all the data. I follow the factory load data. I ordered the Final Finish bullets & plan on trying them when they come in, (~5 wks). I set the trigger at about 3 1/4 lbs. I put a proven Burris FFII 3x9 scope on it. Oh & took the pads off from the end of the forearm of the stock, which almost floats the barrel. Didn't make a difference. I want to buy some new bullets but I'm not sure what to try. Guess I just have to shoot it more...

I just had an urge to look at the crown more closely, & the smith messed it up! Its not even, like the inside chamfer wasn't cut all the way around. I'll be taking it back tomorrow morning. Wish me luck!
 

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That's why you should never have a barrel cut. You are going to need a re-crowning job, and he should do it for free.
 

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Recrown It and You should be good to Go. I have cut XS & XL guns from 16 18 19 & 20 inch barrel they all shoot wounderful . sounds like a bad Crown .
 

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Discussion Starter #5
Taking it up 1st thing tomorrow to have it re-crowned. I should've noticed it when I picked it up. Just goes to show you, just because someone says they're a smith doesn't mean they're good at it. Trust no one until they earn it.
Hawlg, I don't understand your logic. You wouldn't have a barrel cut bc the crown might not be perfect? What if one of your guns had a damaged crown, would you re-barrel it? No disrespect here, I just get what you're trying to say.
Hopefully I'll be reporting back w/ good news...
 

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Good luck! I hope the guy is better at standing behind his work then he was at initially performing it.
 

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Sorry to hear of the problems with your "X" gun carbine. I also think it must be the crown. As you can see, the 'smith did a recessed crown on my gun and as you know, the gun is very accurate.

 

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Discussion Starter #8
Well, the smith looked at the crown w/ his scope & said, "there's nothing wrong w/ this crown". I thought he was smokin crack. He said that wasn't causing my gun to be inaccurate. Then he looked all thru the barrel & found that there is no relief at the end of the lands, they go all the way to the end at the throat. Then he showed me another barrel & how they should look. He said he would re-crown it if I wanted him to, but he's sure it won't shoot different. I told him to do it & he asked that I just let him know how I made out. He did a real nice job on it. He said that if it still doesn't shoot well, to bring an empty round w/ the bullet & OAL I was using & he would cut the lands accordingly. And that should make a big difference. This is all new to me. I'll shoot it on Tues or Wed & go from there...
 

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Discussion Starter #11
Didn't shoot it w/ 22 in. Went right from gun shop to smith. I made up my mind that's what I wanted, so I went for it. I'm off work Tues & Wed. Plan on shooting Wed. I'll post the results.
 

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blzeye said:
Well, the smith looked at the crown w/ his scope & said, "there's nothing wrong w/ this crown". I thought he was smokin crack. He said that wasn't causing my gun to be inaccurate. Then he looked all thru the barrel & found that there is no relief at the end of the lands, they go all the way to the end at the throat. Then he showed me another barrel & how they should look. He said he would re-crown it if I wanted him to, but he's sure it won't shoot different. I told him to do it & he asked that I just let him know how I made out. He did a real nice job on it. He said that if it still doesn't shoot well, to bring an empty round w/ the bullet & OAL I was using & he would cut the lands accordingly. And that should make a big difference. This is all new to me. I'll shoot it on Tues or Wed & go from there...
Since you aren't confident with his work, I would not have him do that second step. I would at least get a second opinion frm someone who is known to be good.
 

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I am new to the forum, but I have been a gunsmith for 30 years, taking over my father's business. I do a lot of barrel work and have cut and crowned many barrels. I usually use either an 11 degree target crown or a straight recessed crown. I have sold a number of Marlin 7's to customers and two years ago I bought one for my daughter. It is an XS7 youth in .308. I shoot 42.5 grains of 4895 behind a 165 Remington core-lokt in Winchester brass with a Federal primer. I worked up this load with the original 22" barrel, chronographed it at 2549FPS average. I then cut the barrel to 18" as was my intention all along. The same load now chronographs at 2395FPS and shoots a five shot group at 100 yards in 7 minutes of .689" average. I used to bench rest shoot in hunter and varmint classes, so you can believe the numbers. I have cut a number of .308's down to 18". Remington 788's, Stevens 200's, XS 7's. Almost every one shoots better than factory, which I think is due as much to shortening the barrel than any craftsmanship involved. Don't get me wrong, the last thing the bullet sees is that crown, so that in my opinion is the most important part of the barrel and has the greatest effect on accuracy. If your crown is fixed properly now, you will be pleased with the results, I am sure.
 

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Discussion Starter #14
Thank you for your input, critters, I appreciate it. I certainly hope you're right, and I can't wait to go shoot it! What do you think about the rifling going all the way to the end of the throat? Do you think that would have a big effect on accuracy?
 

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Having not seen the gun myself, I hesitate to second-guess a smith I don't know. I would find it difficult to believe a factory throat would not be correct in configuration, although I have seen factory headspacing that was incorrect. Looking down the barrel from the action end, you should see the shoulder taper, the case neck ring(or step) a short bit of smooth bore, and then the lands should taper up from there. That bit of smooth bore into the rifling is the throat portion of the chamber, and the rifling should not continue all the way through it to the case neck step. Throating reamers have a long gradual taper that eases into the rifling, however the lands should remain crisp throughout the taper until it reaches bore diameter. The rifling lands should form the grooves in the bullet, rather than cutting them. When this tapered portion of the rifling at the throat becomes eroded, the bullet tends to smear into the rifling rather than the rifling forming nice clean grooves in the bullet. This is a common condition in cartridges such as .220 swift and 6.5'06 that can be loaded to real barrel-burning velocity. It can effect accuracy to a degree, but nowhere near as much as the crown. I personally washed out a Swift barrel in under 500 rounds, but then I was a kid, and I was doing a lot of pretty wild experimentation. I had just read Ackley's book, had an old Apex Swift barrel, a good '98 Mauser action, and dad had a reamer. A set of dies, some old shells, an assortment of every .22 bullet I could find, and I was busy for half my summer between 11 and 12 grade.
An extended throat, known as "freebore", has been used by some, most notably, Weatherby. The thought is to reduce resistance on the bullet, letting it get moving before entering the rifling. I have never been a fan. I personally adjust my seaters so the bullet just contacts the rifling when chambered.
 

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Discussion Starter #16
Re-crowned & shooting MUCH better!

Finally got to shoot the .308 after getting it re-crowned. The first group was 1.1"! That's about a 250% improvement! I tried one load identicle to one I had shot before the crown was fixed & it shot 1", (3 shots @ 100 yds). I didn't write down what the group was before, I just wrote "no good" in my notes. I think it was about 2.5" or worse. I'm going to keep messing w/ different loads, but I'm happy w/ 1" groups for a gun I got primarily for carrying in the woods. That was w/ 150 gr Speer Grand Slam on 43 gr of BL-C(2), & it was rather windy yesterday. I still want to try the Berger 165 gr VLTs.
Thanks for all your help/advice, guys. Now I have to give the 'smith a call & tell him the re-crown job worked!
 

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Glad to hear things worked out for you. My 308 "X" gun carbine also likes 150gr bullets.
 

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glad all worked well after re-crowning. Has the smith done anything else (other than crown)? Does he know the rifle shoots fine now? I ask because he claimed the crown was fine
 

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Glad to hear it has worked out for you. The way you described the original crown job, I was certain it would once it was corrected. I have resurrected dozens of "worn out" shooters by cutting 1/2-3/4" off the end of the barrel and recrowning. Enjoy your 7, they are one of the best new guns I have seen on the market in years.
 

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What does confuse me though is why the gun smith that originally cut the barrel did not do a good crown job on it to start with.

If you used the same gun smith I hope he did not charge you to fix the crown that should have been right the first time.
 
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