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May 30, 2021

Gun Thread: Memorial Day Density Altitude Edition! [Weasel]

DA Card scaled.jpg

Well a great big Gun Thread howdy to all y'all! Welcome to the Sunday Gun Thread! Sit back and relax because for the next few hours we can talk about guns 'n shootin' and forget about the rest of the world for a bit. Do we have any new people this week? We love new people, and especially the 'ette's. Not only do they shoot just as well as the guys, but they generally smell better, too. Regardless of which bathroom you're choosing to use today, we're happy to have you here. Please don't just lurk, say hello!

It is looking like there might be a trip to the farm in the plans this week. I'm waiting for the weather to clear, mostly. As I write this, it's rainy and in the 50's along the mid-Atlantic, so not the best shooting weather. Although it's forecast to dry out and warm up this week, I really need to cut the grass and vegitation and do some other chores, so not sure if I'll get to do any shooting. How about you all? Are you fair-weather shooters, too? Over the years, I have competed in matches in truly miserable conditions, mostly involving days like today, cold and wet, so I don't feel compelled to get out in those conditions when I don't have to.

Tomorrow is Memorial Day. Please take a moment or two to think about the people who paid the ultimate price for our freedom.

With that, let's get to the exciting content below, shall we?


An interesting discussion came up in the comments last week, and that's how the zero of a rifle changes with atmospheric conditions. Nothing has changed inside the gun or with the ammunition, but rather the ballistic arc of the bullet is being influenced by changes in air density. Shooters will notice this effect particularly when traveling from one place to another, but simple changes in local weather will cause it to one degree or another, too. What atmospheric conditions affect air density? Air temperature, barometric pressure, elevation, and relative humidity.

You will recall that zeroing a rifle is making adjustments the sights so the bullet impact at a fixed distance is exactly matched to the sights, or scope crosshair when using optics. Most shooters zero their rifles at 100 yards to make the math easy, or some other fixed distance that is suited to their shooting application. This zero is only valid under the exact atmospheric conditions that existed at the time the zeroing was performed, and with the exact same ammo. Change the air density, and the impact will be high or low, because the bullet is flying through thicker or thinner air. At closer distances of a few hundred yards with smaller air density changes the effect is usually negligible. However, at longer range and with large air density changes the effect can be significant at the target. Everyone is used to adding elevation to a sight or scope to account for shooting at greater distances, but as the zero changes the amount of elevation needed for the ballistic arc of the bullet to match the sights, changes too.

A change in ammunition will affect the point of impact in much the same way, only this time velocity changes take the place of air density changes.

Ballistics and Atmospheric Conditions Affecting Bullet Flight
If you know the weight of the projectile and its velocity leaving the barrel, and certain atmospheric conditions affecting air density then you can compute a firing solution. Most generic range cards use a "standard" atmosphere, from which there are several to choose. I use the ICAO atmospheric model, which is; air temp 59 F, air pressure 29.92 Hg, elevation of 0' or sea level and 78% relative humidity. But what if you're not shooting in precisely these conditions? What if you take a trip from your home range near the beach and go hunting in the Colorado mountains?

Since it's cumbersome to record and use all of that data, it can be combined into the single reference value Density Altitude (or DA) which is simply expressed as a variation in altitude to the standard column of air at sea level. If you have been faithfully recording data in a little notebook every time you shoot, you should have been including the DA, range to target, and the necessary elevation in MOA or mils for future reference.

Density Altitude is published for local airports, and many online calculation tools exist, but you need data in real time as the DA changes throughout the day. If you're interested in this level of precision, I strongly recommend investing in a Kestrel Meter a compact weather instrument with an anemometer and which calculates DA based on your current conditions at the range.

If you have been recording your data, all you need to do is look in your data book and find the last time you shot at the same distance with the same rifle and ammo, and use the same elevation based on DA. It doesn't matter where on the planet you observed the data, if accurately measured, it will still be valid. If you are diligent, over time you will record enough data to cover most shooting situations. I made it a habit to note my scope elevation at the end of every match and record it with the current DA as soon as I came off the line, and kept the notebook in my range bag. Next time, I'd measure the current DA and look up the required elevation for that condition in my notebook.

A number of good ballistic computers are available to assist the shooter. Ballistic is the app I use on my smartphone. I believe the Standard Edition is still free and includes an exhaustive bullet library for reloaders. It also allows you to input atmospheric conditions, among other variables, to customize the firing solutions to your present conditions. It's a very slick product and bigly useful, just never use an electronic device on the firing line in a match. I prefer my little notebook as it's absolutely accurate based on my rifle and ammunition, and it's much easier to measure the DA and find the corresponding recorded reference value instead of fiddling around with the phone.

Try it and let me know what you think!


First up, our pal Scuba_Dude has been back to the Sig Sauer Academy in Epping, New Hampshire for their Handgun 103 course. SD completed the prereqisite Handgun 101/102 last year and was ready to up his game. Let's find out what it was like.

First off, we had 2 instructors Joe and Bob. Both former LEO. They were great instructors, they were patient with us and made sure we understood what was being done and giving tips and critiques when necessary. The first hour of the class was in a classroom where they introduced themselves and their back ground and then went around the class asking us our name, where we were from, what we did for a living, what we were expecting to get out of the class and what we were shooting. There were 9 of us in total. 1 female who was probably in here early 30's and the rest guys ranging from late 30's to early 60's. They then went over all the rules and paperwork that needed to be done before heading outside to do the fun stuff. This probably took 45 minutes to an hour.

Handgun 103 had us always drawing from a holster. We were at the 3 yard line and we all drew from the holster, presented, pressed (pulled trigger) and fired one shot, checked our status and checked that our trigger finger was up high on the frame then holstered the gun and kept repeating that for a full magazine.

Being that I was shooting my P226 I was always making sure I de-cocked the hammer before holstering. Another drill they had us do was go back to the 5 yard line, draw and shoot 5 shots at the 8 inch circle in the target, then back to the 10, then 15, 20 then 25 yard line. I will say I did good until I went past 15 then my shots were all over the target.

They gave us 3 dummy bullets to load into our magazines so we could practice the drill when you have a failure to fire. I think I got pretty good at that, And from then on we always mixed the 3 dummies in with our live rounds so anytime during the drills we were experiencing a failure to fire, so we would have to tap, rack and continue. And on one drill the instructors put a spent casing in our gun to mimic a stovepipe, we would then load a full magazine, holster the gun and do the drill to clear a failure to eject. We did that about 3 times.

They had us do target transitioning where we would draw, shoot a steel plate, transition to another steel plate either to you left (if you shot the right first) or your right. I will be honest, I did poorly at this. I kept on shooting the first plate and instead of keeping the gun out in front of me while I transitioned to the next target I would pull the gun back to my chest and get my eye on the next target and press the gun out and take the shot. Something I really have to work on.

The next set of drills had us moving then shooting. We would face the target, the instructor would call out FORWARD and we would take one step forward, draw, shoot, check status, check finger, holster. We would then repeat when he called out another direction like Back, left or right.

The next drill was shooting one handed with our dominant hand. We would do 5 shots with the gun straight up and down, the next 5 with the gun canted 7 - 10 degrees. Then 5 with the way we felt most comfortable.

The final drill were of us shooting with our non dominant hand. We would draw from the holster then we would have to transition the gun to our non dominant hand being careful NEVER to put a finger in the trigger well. We would shoot 5 shots with the gun straight up and down and another 5 with the gun canted 7 to 10 degrees. Can I say I felt awkward doing this? All the times I shot off hand where with me picking my gun up from the bench with my weak hand and shooting. Drawing with my dominant hand and transitioning to the weak hand was VERY awkward.

All in all, I had a GREAT time and I really think I learned something.

Very nice report, Scuba_Dude! Thank you! These are a lot of great drills which everyone can take to their own range to practice.


Next up we have a nice range report from out pal DB-just DB.

I recently returned to the shooting sports after a long absence. Here is a recent effort with my Smith & Wesson Model 686+ revolver. It is a .38SPCL/.357 Magnum with a 2.5" barrel. Basically, it's a snub-nosed .357 Magnum. It's got a satin steel finish and rubber combat grips. The '+' means it holds seven rounds.

DB 1 053021 SW 686 scaled.jpg

DB 2 053021 target scaled.jpg

The revolver is a pleasure to shoot. The L-frame gives it some serious heft, and I found the recoil when using Magnum ammunition to be less than I remembered with my old Model 27. The target was set at seven yards, and I shot both single- and double-action.

Nice shooting, DBjDB! I love the snubby!


Next up, our pal GWB made an online discovery, and sounds like it's perhaps not a good one. Let's hear what he has to say.

I found a great website today! They had oodles of firearms! They had the ones I have been looking for, and at great prices. Yeah, me too. I put some in my cart, then sorta got ... gun shy about giving them my CC if I checked out. I had registered for an account. And an hour later, still no welcoming email in my inbox. Hmmmm.... So, I went and googled "gunsshoppers.com". A couple of places listed them as very low trust. Commenters made mention of things like "Yeah, he told me he no longer takes credit cards, and wanted to be paid via PayPal friends and family." One had to work to get money back as nothing ever shipped. The thing that really made me hesitant? The website was awful in a couple of ways. There were bits that didn't look like an English-speaker wrote them. There were old-style search-algorithm-gaming bits; just inserting "Buy Ruger" and various search terms in blocks of text labeled as "products we offer". There was no way to filter once you got to the point of, say, "revolvers" or "semi-automatic pistols." That the website came to be in July of last year wasn't a deal-killer. I bet there's lots of gun websites that have popped up in the last 18 months. And, of course, that they had 1,057 revolvers evidently in stock, NOTHING was marked as out-of-stock, made me really wonder. Oh! They also had machine guns for sale! I didn't dig into that, but I wonder if that was another clue. They made initial noises about them being legally transferrable or something like that. Anyway, just thought I'd pass it along. I have 2 firearms sitting in their cart. We'll see if I ever get an email about them. They're exactly what I wanted, too. Meanwhile, some other sites just keep delivering when I buy.

Excellent report, GWB. Thank you! It's still buyer beware, everybody. If it sounds too good to be true, it very likely is. If something sets off you bullshit detector, check it out before you get involved with a potentially less than reputable outfit. I took a peek at the website and have to say it's pretty goofy, enough so that I'm not going to link to it. Anyone else heard of them?


Remember our new video pal Lena Miculek from last week? Well here is a great video of hers on how to best use 50 rounds in a practice session.

I really like Lena's videos. She has an easy and confident style that isn't easy to pull off unless you really know the material, which clearly she does. With the ammo situation such as it is today (fyi - getting better but not out of the woods, yet) this is an excellent lesson on how to make the most of the precious commodity.


And speaking of the Miculek's, here's our pal "Jer" bitch-slapping us with some knowledge on concealed carry and the proper draw.


Ax Weasel
Have a question? Ax Weasel! This week we have a question from our pal Neon Madman.

I vaguely remember that you did a thread on gun cleaning a while ago. I have always used Hoppe's #9 and a lot of brush work to clean my guns, particularly the revolvers. It can take a lot of work to get rid of the carbon ring that builds up in a .357 shooting .38 wadcutters - or, for that matter, in a .38 shooting .38 wadcutters as well. I see that some guy on the internet (actually, it was you) has recommended several times using a product called Wipe-out, mainly for copper fouling, and letting it soak overnight. The promo blurb for it claims that it is also good for carbon, black powder fouling, etc - like any other product blurb, it makes the stuff sound like magic. Let it sit overnight, then just patch the gun clean. What do you think? How does it compare to the old-school version of gun cleaning with #9 and a crapload of brushing?

Weasel Sez:
Thanks Neon Madman! Do I ever recommend Wipe-Out! It is an amazing product, and I only recommend things I have both used and liked. You literally just spray it into your barrel, let it foam up and sit overnite, then patch it out the next morning. When I was traveling all over to matches, this is what I'd use back at the hotel in the evening and it worked very well, with zero scrubbing. I have not tried it on handgun barrels but I'm certain it would work equally well in that application. I do recommend plugging the chamber end of the rifle with a cleaning rag or something similar and spraying from the muzzle end to keep the crud out of the chamber and trigger assembly. It also works well as a solvent in your normal cleaning routine without leaving it in overnite. Give Wipe-Out a try!



TDG scaled.jpg

The social and cultural event of the season, NoVaMoMe 2021 is on the calendar! That's right, you people have a chance to meet many of your online pals on Saturday, July 24th beginning at 1pm until dark, or such time as it gets busted up by the cops. We have an exciting new location in the Northern Virginia area which we think will be more better than before and allow extended time for visiting. Admission is $25 which includes food and soft drinks, with a cash bar. This year all of the food is prepared from the greatest non-fiction literary work in modern history, The Deplorable Gourmet. Want to find out if your recipe made the cut? Want to be one of the cool kids? Just send an email to novamome at protonmail dot cee oh emm, pass the rigorous screening process to obtain registration details, then sign up to attend! Easy-Peasy!

It promises to be a great day, including our customary raffle of AoSHQ themed gift baskets. That's right! Each of the AoSHQ weekend threads has a specially themed gift basket chock full 'o theme related gifts!

Win a Dream Date with Weasel!
This year, a separate raffle for the Gun Thread gift basket will be held. This fabulous prize includes an entire day of shooting and personalized one-on-one handgun & rifle coaching and instruction at Weasel Acres on a mutually agreeable date with yours truly. The lucky winner will be able to not only bring and shoot their own weapons, but also try out a variety of WeaselWeapons using WeaselAmmo! The winner will take home 150 rounds of quality 9mm ammo to practice what they have learnt, a signed photo of WeaselDog and Fun Size Joe, and a complimentary video of the WeaselAcres experience, as parting gifts.

We will end the day with dinner at a good Mexican place in nearby Appomattox. Pretty much a dream date with Weasel! The winner will be responsible for their travel to and from Central Virginia, hence the separate drawing.

Don't be a pathetic girly-man loser, register today!



I'm really very seriously not kidding around anymore. Buy Ammo
AmmoSeek - online ammo search tool
GunBot - online ammo search tool
SG Ammo
Palmetto State Armory
Georgia Arms
Target Sports USA
Bud's Gun Shop

***Mail Bag***

This week our Mail Bag entry comes from out pal Hrothgar. He hates those watermelons!


Please note the new and improved protonmail account gunthread at protonmail dot com. An informal Gun Thread archive can be found HERE. Future expansion plans are in the works for the site Weasel Gun Thread. If you have a question you would like to ask Gun Thread Staff offline, just send us a note and we'll do our best to answer. If you care to share the story of your favorite firearm, send a picture with your nic and tell us what you sadly lost in the tragic canoe accident. If you would like to remain completely anonymous, just say so. Lurkers are always welcome!

That's it for this week - have you been to the range?

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