March 22nd, 2016

Vertical Fliers? Poor Ignition May Be the Cause…

USAMU Handloading vertical dispersion ignition rimfire accuracy firing pin
Top to bottom – Remington firing pin assembly with ISS, Tubb SpeedLock alloy-composite system without ISS (current versions have dual, opposite-wound springs), and Remington short action firing pin assembly without ISS.

Each Wednesday, the U.S. Army Marksmanship Unit publishes a reloading “how-to” article on the USAMU Facebook page. Last week’s “Handloading Hump Day” article covered mechanical issues and related ignition irregularities that can cause vertical fliers even with good ammunition in an otherwise excellent rifle. We highly recommend you read this article, which offers some important tech tips.

USAMU handloading hump day

Vertical Dispersion: Mechanical/Ignition Issues?

Poor or inconsistent ignition has long been known to be one of the “usual suspects” when one encounters vertical fliers that just shouldn’t be there. By having a sense of some of the basic principles involved, and a few basic areas to check, the shooter may avoid colsiderable frustration, not to mention time, expensive loading components and barrel wear.

USAMU Handloading vertical dispersion ignition rimfire accuracy firing pinIs your well-built rifle of high-quality components plagued with vertical fliers across more than 1-3 handload combinations? Consider the bedding, crown and scope/sight mounts. Are they correct? If so, then you might check for ignition issues before boldly undertaking an extensive, expensive, and quite possibly fruitless quest for the “magic handload”.

SEEING IS BELIEVING: While the author had been aware for many years that poor ignition should be considered and ruled out when dealing with vertical fliers in an otherwise-excellent rifle, actually seeing the problem and its almost instantaneous cure really drove the lesson home.

He was working with a “dot” rifle – a .22 LR match rifle that really stacked bullets into little piles at 50 yards and beyond. With one lot of ELEY Tenex, it produced consistent “bughole” groups at 50, but with another, selected lot of Tenex, similar groups were regularly ruined by single, vertical fliers that did not appear in other rifles. Rather than spending days burning up expensive, select ammunition looking for “magic lots”, he contacted a well-respected rimfire gunsmith and explained the situation.

Without so much as batting an eye, the highly-experienced ‘smith tore into the rifle’s action, and quickly found the cause(s) of the problem. He discovered a demonstrably weak firing pin spring, plus a chip out of the face of the firing pin where it contacted the cartridge rim.

After replacing and tuning the offending parts, the rifle immediately began shooting tiny, bughole groups with the previously “unacceptable” lot of Tenex. Centerfire rifles can also benefit from ensuring positive, consistent ignition. A wise riflesmith is literally worth his weight in gold!

So, what are some issues we as shooters can inspect in our rifles to help determine if ignition woes could be part of our problem? At the club level, ask yourself if that “experienced” Remington, Winchester 70, or even Springfield-based match bolt gun you’re using is still running its’ original 40-80 year-old factory striker spring? If so, a new replacement is cheap insurance against current or future problems. (And BTW, it might be best to stick to the normal, factory-spec spring weight. A super-powerful spring can cause vertical, just as a weak one one can.) Along with that, a routine check for proper firing-pin protrusion is a quick preventive measure that can rule out potential issues.

Other areas to consider are the centering and consistency of the firing pin’s operation in the bolt. Admittedly, with the increasing use of precision-machined custom actions, this is becoming less an issue every day. Below is the firing pin assembly from a custom BAT action:

USAMU Handloading vertical dispersion ignition rimfire accuracy firing pin

However, particularly with factory actions, a very quick and easy check is to remove the bolt, let the firing pin go forward, and look at the firing pin tip through the firing pin hole. Is the tip off-center in the hole, and possibly striking it as it moves forward? Is the hole out-of-round or burred from being struck repeatedly? If so, a trip to the riflesmith is likely in order.

Similarly, machining issues in the bolt/firing pin system can lead to rough and erratic firing pin movement, in which the firing pin drags against an internal surface of the bolt. In high-quality rifles these issues are relatively rare, but not unheard-of, and it takes mere minutes to rule them out. It may be worthwhile to remove the cocking piece/firing pin/spring assembly and look for any unusual gouges, dings, peening, burrs or signs of abnormal wear.

This task is especially easy with Winchester 70s, Springfields, and the similar Mauser 98s, involving little more than the push of a button and unscrewing the cocking piece assembly. This is just one of the many reasons these tried-and-true actions have earned such a loyal following in the field, among hunters who must maintain their rifles away from a shop.

USAMU Handloading vertical dispersion ignition rimfire accuracy firing pin

Particularly with older rifles, watch for and remove excess grease (or even Cosmoline!) from both the firing pin assembly and inside the bolt. This can help improve firing pin speed and consistency. Other bolt-action designs may need a take-down tool or other measures.

As part of this inspection, AFTER ENSURING THE RIFLE IS UNLOADED, slowly cock the rifle, dry-fire, and repeat several times. Listen carefully near the action for inconsistency in the sounds it generates. Does the striker falling make the same sound each time? Do you hear or feel grinding upon operation? If so, where?

Be sure to check the operation of the cocking piece (bolt shroud), firing pin within the bolt shroud, the cocking piece cam and the rear of the bolt body where the cocking piece cam operates. As with our examination for abnormal wear marks discussed above, look for marks indicating roughness or a possible need for light polishing. Then, clean and lightly grease the bearing surfaces while you’re at it.

Remington 700 bolt shroud and cocking cam
Rem 700 bolt cocking cam

These are relatively easy checks that shooters can undertake to perform a preliminary inspection on their own. Other mechanical issues can also cause ignition issues, chiefly centered around the action of the trigger, sear and sear spring. If these are suspected, a trip to an experienced, qualified riflesmith for diagnosis is recommended. We hope you find this information helpful! Join us again next week, and in the meantime, enjoy the shooting sports safely!

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March 22nd, 2016

Hearing Loss and Ear Protection — What You Need to Know

hearing protection ear muffs NRR earplugs osha deafness

Hearing loss can be progressive and irreversible. If you are a shooter, this is serious business. You need to use effective hearing protection every time you go to the range. Even if you are away from the firing line, gunshot noises can damage your hearing. Good foam earplugs costs mere pennies but they can prevent deafness in your later years. Many folks also wear muffs over plugs. Some other shooters prefer the custom-molded ear plugs. Electronic muffs can be useful when you are away from the firing line because they allow you to converse.

Here are some comments from Forum members on the subjects of hearing loss and the need for proper ear protection. You can join the discussion in this FORUM THREAD:

“If you are young and don’t want to end up with profound hearing loss like I have… ALWAYS ALWAYS ALWAYS use hearing protection. This is from a guy who is social security/medicare eligible, has two Re-Sound aids at a not so cheap $2000.00 EACH… and now has religion! When I was young [we] never wore ear gear and laughed at the ringing after 100 rounds of 12 gauge at the skeet range. Now we live with the consequences. Be smarter than I was!” — Gary0529

“Take it from a 70-year-old that has been shooting 49 years. I now have a Re-Sound hearing aid in the left ear and a Cochlear Implant in my right. I still cannot hear. Custom molded plugs are best. Some are sold at gun shows and some are made by the folks that make hearing aids. They are cheap as compared to this $200,000 implant. DO IT NOW for everyone around guns.” — Richard King, King’s Armory

“Say WHAT? You have to type a little louder! I used to shoot without any muffs, when I was ‘young and indestructible’, and now I have about 40% loss. When I take youngsters and friends shooting, they get muffs and plugs. I’m not allowed suppressors where I live. I would use them if I could.” — Josh B.

“For what it’s worth, I wear both ear plugs and muffs that have NO sound adjustment capability. As a youngster (15) I wore no ear protection either in shooting or motorcycle riding. I kept doing that until entering military service at age 18 where we had to wear ear plugs at the range. Started wearing ear plugs after that, except when motorcycle riding. At around age 53 my hearing started going south as a result of my own stupidity as a youngster and now some 15 years later I only have about 45% of my hearing left. So beware all — there is a price to pay if you don’t protect your hearing.” — Shynloco

hearing protection ear muffs NRR earplugs osha deafness

Important Safety Considerations:
1. The NRR (noise reduction rating) is determined by “experimenter” fit, not user fit, and trained listeners during the testing period. This results in inflated protection numbers compared to real-world protection.
2. Any disruptions in the protector/skin seal will greatly reduce the effectiveness. Think eye glass temple bars, lots of hair, ear wax, etc. A 5% leak results in a 50% reduction in effectiveness.
3. Double protection gives only 5-10 dB extra protection.
4. Bone conduction gives about 50 dB protection so hearing protectors are the weak link[.]
5. Keep the protectors in/on your ears. Over 8 hours, if you remove them for only 30 minutes (cumulative), the effective protection is cut in half.

So, if you are using a really good muff with NRR of 33 and a foam plug with NRR of 27, the real-world NRR would be about 35 dB, at best. This would attenuate a gunshot by that amount. The key is time versus exposure. Limit the exposure and you limit the dose. — DelS

Ear Protection for Small Children
Don’t forget to protect your kids if you take them to the range (or loud rock concerts). Parents of very young infants should consider Baby BanZ Muffs, which are designed for infants 0-2 years. These small-sized muffs can protect toddlers’ hearing when loud machinery is running, during fireworks displays, or other noisy activities. These really work for tiny tots. One mother reports: “I bought these for my two-month old and they work great! He’s never fought us putting them on. He’s now falling asleep with them. He’s slept through a demolition derby and a rowdy wedding reception. I’m ordering another pair for my nephew.” Another mom says: “We bought these when we took our four month-old to a loud event. They fit her head well and were well-padded. She looked very comfortable, so comfortable in fact that she slept for most of her first rock concert. I’d say they worked exceptionally well!”

Baby BanZ ear muffs kids
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March 22nd, 2016

Krause and Gun Digest Books at Midsouth

Krause book reloading shooting midsouth resource

Midsouth Shooters Supply now carries the full line of shooting and reloading books from Krause Publications at very attractive prices. Looking for reliable reference works on reloading, or a gift for a shooting buddy? You’ll find something worthwhile among the Krause library of gun books, which includes the respected Gun Digest Shooter’s Guides. Match directors also take note — books make great match prizes. Paperback books cost no more than wood plaques but they will provide valuable information for years instead of just gathering dust in a closet. If your club offers training programs, Krause offers many titles that will help new shooters improve their skills.

Here Are Some of our favorite Krause Shooting and Reloading Titles:

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Krause book reloading shooting midsouth resource Krause book reloading shooting midsouth resource
Krause book reloading shooting midsouth resource Krause book reloading shooting midsouth resource
Krause book reloading shooting midsouth resource Krause book reloading shooting midsouth resource
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