The Firing Line Forums

Go Back   The Firing Line Forums > The Hide > The Art of the Rifle: General

Reply
 
Thread Tools Search this Thread
Old October 11, 2018, 07:05 AM   #26
Picher
Senior Member
 
Join Date: December 14, 2004
Location: Maine
Posts: 3,694
As to the claim that the last shot fired out of a magazine is a flyer, consider that cartridges in the magazine provide upward pressure on the forward part of the bolt, contributing to alignment with the bore. Changes in bolt position can cause variations in firing pin impacts with relation to the cartridge rim, hence affecting accuracy.

Examine the relative firing pin impacts of the last shot verses other shots. If there's a difference, consider modifying the firing pin, especially to impact a bit below the roll of the rim, regardless of the last shot fired. Since there's no priming compound at that point, the firing pin strikes will be deeper and more uniform if the top of the firing pin strike is just below that fold.

I learned that trick when accurizing 10-22s and modified my CZ firing pin, as described, and it made a difference in accuracy.
Picher is offline  
Old October 15, 2018, 06:54 AM   #27
Mobuck
Junior member
 
Join Date: February 2, 2010
Posts: 6,846
I opened another full carton (2010 production)of Hornady 17 grain V-max yesterday and from the first box had 1 hangfire and numerous split neck/shoulder cases. I also discovered two different colors of the plastic tips which produced different POI within the same box. Six of the 10 boxes in the sealed carton pack contained the varied color tips.
Lack of accuracy and POI shift was so serious that I just stopped shooting the 17 until I dig out some different ammo.
Mobuck is offline  
Old October 16, 2018, 08:43 AM   #28
Picher
Senior Member
 
Join Date: December 14, 2004
Location: Maine
Posts: 3,694
Mobuck: Did the unfired ammo have split neck/shoulder or fired cases?

My neighbor has a Savage .17 HMR that splits almost all cases. I suggested she return it to the dealer and it be sent to the factory for a new barrel with a verified chamber/headspace.
Picher is offline  
Old October 16, 2018, 08:02 PM   #29
Mobuck
Junior member
 
Join Date: February 2, 2010
Posts: 6,846
Splits only after firing. Happens in all three rifles we have (77/17, RAR 17, and CZ Scout switch barrel). Doesn't happen with fresh CCI or Winchester ammo.
Mobuck is offline  
Old October 30, 2018, 01:53 PM   #30
Picher
Senior Member
 
Join Date: December 14, 2004
Location: Maine
Posts: 3,694
I'm having a great time with my .17 HMR barrel on my CZ 455. Winchester isn't bad, but Hornady seems to be the most consistent, though some Lots aren't as good as others. I might get one flyer out of 8-10 rounds, but the rest are MOA or better. Having a blast with the little round, but have yet to have the occasion to use it on varmints, which is the main reason for buying the new barrel. Had it out on the range when sighting-in my .270s last week and put two shots about 3/8" apart an inch to the right at 100 yards, made adjustments to the scope and the next shot was a PINWHEEL. (I'm not so dumb as to shoot another shot. Ha ha.)
Picher is offline  
Old October 31, 2018, 07:45 AM   #31
J.G. Terry
Senior Member
 
Join Date: January 24, 2014
Posts: 577
Winchester Ammo

Winchester 17 HRM ammo: Come to think of it the 93R17 had been shot in a while. All I could find at Wally World was Winchester. Had four maybe five misfires in fifty rounds. Perhaps, that had gone sour in the store. Looks like age does these rounds no good.

I have the 93R17 and a 22RF BSEV. These rifles are ammo sensitive. Try to shoot any old thing in these guns and you will go nuts for accuracy. That is, unless you are lucky. I have to ask myself what is the reasonable rifle accuracy. I have to ask what is my limit of my reasonable accuracy. I find the latter is the problem frequently. That would be with the right cartridges. Not here but you can get misled by accuracy claims on the net.
__________________
Intentionally Antagonizing Another MemberInsults and Ad Hominems

Last edited by J.G. Terry; October 31, 2018 at 07:47 AM. Reason: SOS
J.G. Terry is offline  
Old October 31, 2018, 08:56 AM   #32
Zen Archery
Senior Member
 
Join Date: January 30, 2005
Posts: 274
after it gets hot... but its a .17HMR....
__________________
Video Hunting Library
Zen Archery is offline  
Old November 1, 2018, 10:48 AM   #33
Picher
Senior Member
 
Join Date: December 14, 2004
Location: Maine
Posts: 3,694
For those folks using .17 HMR: How often do you clean your bores? If you're used to shooting .22LRs and not cleaning bores because they're coated with wax from coated bullets, you may be surprised that your .17 HMR bore may be rusting, after shooting and putting it away dirty. This applies even more so to those who live in humid areas/times of year.

It may not be necessary to scrub the bore, but consider running a patch through it with Break-Free or some other rust preventative, preferably starting from the chamber. Running a dry patch through, or just firing a shot could better assure zero for the next shot.
Picher is offline  
Old November 1, 2018, 12:22 PM   #34
Zen Archery
Senior Member
 
Join Date: January 30, 2005
Posts: 274
i only clean when it gets really wonky. which ive learned is around 500-600 rounds.
__________________
Video Hunting Library
Zen Archery is offline  
Old November 1, 2018, 07:38 PM   #35
Picher
Senior Member
 
Join Date: December 14, 2004
Location: Maine
Posts: 3,694
Although bores get metal fouling when fired, the worse part about not cleaning is that they become unprotected from moisture/corrosion. When they get corroded, the next firing accumulates more metal fouling.

Fouling isn't as noticeable, nor harmful when the surface area is a relatively small area, compared with the mass of the slug. However there's a big difference in a 17 caliber, compared with, say a 30 caliber, so a little fouling can have a lot more effect on accuracy/pressure.

I'm of the opinion that we need to keep .17 HMR bores and chambers clean and protected very well, or they can not only lose accuracy, but increase pressures.
Picher is offline  
Old November 3, 2018, 06:02 AM   #36
Mobuck
Junior member
 
Join Date: February 2, 2010
Posts: 6,846
The 17 HMR is one of the most finicky about a certain level of fouling that I've seen. Some like to be fairly clean and some do better with several shots after cleaning. Maybe not as bad as one 22lr I have that takes 50 rounds to "get back in the groove" but my 17 HMR's don't like being clean.
Mobuck is offline  
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 07:34 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2021 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Page generated in 0.04667 seconds with 10 queries