| Author | Message | ||
     Rick_a |
This is how "they" think. All of them. https://www.youtube.com/watch?v=FigrthdKGAk It turns out my 10.5" AR firearm did not fit in my usual backpack...so my tiny flash hider went there instead. I'm getting this tiny A2 for the 16" rifle, instead.  | ||
| Rick_a |
My 10.5" firearm in the current guise.  20191123_182353 by Slick_Rick77, on Flickr Threw some rounds down range today. Was good. The empties just cartwheel out unenergetically but it functions perfectly and locks back on an empty mag. The muzzle blast is enough to turn the target horizontal, but there's no visible flash to speak of...amazingly. | ||
| Aesquire |
Pity I'm not in a free state so I could buy some of your cast offs.  May be of interest. | ||
| Rick_a |
I caught that. Cool from an engineering perspective...unnecessary from a practical one. People have been tuning port sizes, buffer and spring weights, and upgrading extractors for decades to deal the compromises made in shortening AR's. For regular full auto use it would be good...but that's not really the intended role for a standard infantry rifle. The auto position was generally used only to expend blank ammunition in a timely manner. | ||
| Rick_a |
This interests me...the resurrection of the Cav-15 Mk3. https://www.youtube.com/watch?v=G6Rd6BKaJDo | ||
| Gregtonn |
Anyone fired either of these? https://ruger.com/products/ar556MPR/specSheets/853 2.html And for Rick: https://ruger.com/products/ar556Pistol/specSheets/ 8571.html G | ||
| Rick_a |
The MPR is an amazing value. I'd change the muzzle device to something more tactically sound...but throw on your optic of choice and some flip up backup iron sights and it's done. As for the pistol, I'd do the 10.5" 5.56. I ain't got time for no niche cartridges. | ||
| Ourdee |
I question the twist rate in those Rugers. I have a 1:9" in my AR pistol. Ruger says they have a 1:16" twist in both of those. | ||
| Gregtonn |
Niche cartridge...sort of. The .350 Legend is basically a 5.56 case with the neck cut off and stuffed with a .357 bullet. The bullets are a bit specialized because most .357 pistol bullets have a hard time handling the velocity. With the millions (billions) of expended 5.56 cases out there the .350 should catch on rather quickly. G | ||
| Rick_a |
The Rugers use a 1/8 twist in their 5.56 guns. If it's not available in bulk or at the average sporting goods store relatively inexpensively...I'm inclined to not own it. | ||
| Ourdee |
Now, if they made it in .454 Casull at that price, I'm all in. | ||
| Gregtonn |
RD, The reason for the lower twist rate in your AR is due to the higher velocity of the 5.56. High velocity bullets tend to come apart at high twist rates. Lower velocity bullets tend to be more accurate at higher twist rates G | ||
| Ourdee |
The 1:9" is a higher twist rate than the 1:16". At 2800 feet per second a 1:9" twist barrel will spin the bullet @ 226,800 RPMs. At the same velocity a 1:16" twist barrel will spin the bullet @ a meager 126,000 RPMs. | ||
| Ourdee |
1:9" I chose for the 11.5" barrel was supposed to be a great match for the 40 to 62 grain bullets I planned on using with it. If I thought I would have easy access to MK262 77 grain OTM I would prefer 1: 7" for the twist. I do not intend on shooting past 300 meters with this AR. I really intended the build for 100 meters of less. It is great within that range. I feed it M855 bulk ammo and hold a few mags of .223 hollow points in and near it for home defense. It has ate all the different ammo I've fed it with out a problem. | ||
| Ourdee |
Twist rate needs to be faster as the bullet length increases. | ||
| Aesquire |
It's bullet length that needs different twist rates. With lead core "normal" bullets, length and weight are directly related. A 62 grain is longer than a 55 grain, all else being equal. Longer, faster twist, spin it faster, more stable. Monolithic copper and other alloy bullets can be longer than the same weight lead core bullets, and need faster twist to stabilize. Cheap, thin wall light lead core bullets can be spun too fast and even disintegrate shortly after leaving the barrel. 1 in 16 was the original M-16 twist. Rapidly changed to 1 in 14 because cold weather, denser air, gave bad accuracy. When the military switched from 55 to 62 grain, they changed again. 1 in 12 would have worked, but to accommodate tracer ammo they went to 1 in 7. https://nyfirearms.com/blog/2010/03/ar-15-barrel-t wist-rates-which-is-best/ IMHO 1 in 9 is fine with up to 62 grain lead core bullets. Some 66 grain work fine. 1 in 8 is good up to 77 grain. Or better, I haven't tried longer ones. All work fine with 55 grain. I have seen 50 grain thin wall bullets just turn to powder out of A 1 in 7 twist barrel, the centrifugal force tearing the bullets apart, visibly, just a few yards from the muzzle. Those were handloads, using bullets intended for slow twist .22-250 barrels. ( 1 in 12 ) Afaik, no reputable company 55 grain tipped 5.56 ammo has that problem, and the maker would mark the proper twist if needed. Example is Varmint Grenade 50 grain frangible core copper bullets. They call for a 1 in 10 or faster barrel on the box. I'd use 1 in 8 or 7. They are very long for their weight, longer than the 62 grain OTM I liked in my 1 in 9 rifle. So it's length. Not weight. | ||
| Rick_a |
Wasn't aware of this...disappointing. The Supreme Court refused to hear what should have been an important case. https://www.youtube.com/watch?v=41EsP2wJacc Bullet weight makes a good general guide for rifling twist. It's really a matter of weight, profile, and weight distribution. | ||
| Ducbsa |
I just saw a WW2 show on TV and some of the Thompsons had the drum magazine. The AR drum magazine is supposed to jam easily, the Thompson mag must have worked better to be suitable for combat vs. range fun? | ||
| Aesquire |
Not real!y. The drum was heavy, only somewhat reliable, and most importantly, expensive. Also hard to carry. Big round drums are space hogs. Sticks stack nicely in Pouches. When they went from the stupid expensive 1928 to the simplified, but still expensive M1 Thompson they dropped the drum magazine cuts in the receiver. But the Thompson was a big heavy expensive gun still. Lots of machining steps, carved from big slabs of metal. That's why they went to the M2. Never heard of it? That's because they hadn't worked out the bugs before the stamped sheet metal M3 was ready, so the M2 saw very limited use. And the mags were sorta copies of the Sten mag, double stack, single feed. Bad design. Hard to load. The Sterling used a double stack, double feed magazine. Far superior. Drums were just too bulky and a space wasting shape, Hard to carry in pouches. They even had a wood frame backpack to carry drums in WW1 that was stupid, since the Other guy had to pull mags for you, or himself. ( not the Thompson, which came later ) Everyone, even the Russians, gave up on drum mags. They just cost a lot more than box mags. | ||
| Natexlh1000 |
They ditched the drum in favor of the stick magazines. Also, they simplified the crazy Rube Goldberg Switch watch mechanisms for ease of rapid manufacturing. Remember that when the Thompson came out, it was really cutting edge. Another difference is the shape of the rounds..45 are almost cylindrical whereas the .223 is conical. Easier to stack a bunch of cans compared to cones. I read that the Aurora movie theater ••••••• would have gotten more victims but his drum magazine jammed. Speaking of jamtastic, Check out Nork helical magazines:  Perhaps they fear bananas? | ||
| Aesquire |
The exception was & is squad automatic weapons where a big drum or box is better than a loose belt, since one guy can pick up and move with one attached to the machine gun easier than with a belt flopping around, tripping you, catching on everything, then jamming. Box with belt curled up inside has been used since WW1. Even the lightened Browning 1919 was a total pain to move with. There's a reason guys got Medals of Honor for picking them up and running up to A machine gun nest in the Pacific theater. Compare the big bad Browning or they BAR to later RPK. Or Stoner 63. The Browning 1917-1919 was a fine weapon! But it's a Crew Served belt fed machine gun. You need a loader to keep feeding it, and hopefully a whole squad to Helsinki and the heavy tripod. See Guadalcanal, where 2 seriously wounded men held off multiple human wave attacks at night with one. When found in the morning there were over 200 enemy bodies in front of and around them. Edited for space & details, see below. (Message edited by Aesquire on November 26, 2019) | ||
| Aesquire |
https://www.historynet.com/marine-sergeant-al-schm id-september-96-world-war-ii-feature.htm | ||
| Rick_a |
A slightly less capacity magazine is much handier than a drum. 40rd box magazines make a good compromise. I need to get one, one of these days. Modern belt fed SAW's use a encased belt or pouch. My favorite sub gun, the Colt SMG, uses an UZI mag with a different catch. Funny how successful magazine designs (and firearm, for that matter) hold up to the test of time. Our most modern and successful designs have been around several decades...some have been around since the turn of the last century. The Thompsons A1 style guns with alloy receivers look interesting...though not enough for me to get one. They were surpassed quickly, save for the notorious gangster use. I recently learned that the BAR was originally designed as a closed bolt. The action has been the basis or inspiration for a few open bolt belt fed guns, interestingly enough. I wonder if Browning ever envisioned so many of his designs having such an enduring legacy. It's quite remarkable. Doing some traveling for the holidays...I find it interesting how simply traveling from one state to the next can result in the abandonment of some of our most basic Constitutional rights. | ||
| Ourdee |
I find it interesting how simply traveling from one state to the next can result in the abandonment of some of our most basic Constitutional rights. I have to look up laws prior to going on trips. My rights remain my rights no matter what laws have been used to try and take them. If I was President, jury nullification would be taught. Judges too often tell lies. Police too often tell lies. I have come to believe that there are a lot of people with no qualms against telling lies. Jury nullification is the last great check and balance. | ||
| Rick_a |
H&K's public media people set up a "Gun Jesus" poster for Ian McCollum some months ago. The interwebs has branded him as such some time ago. It's pretty cool.  | ||
| Rick_a |
Something. It's rather silly that what's a simple right in most states is a felonious violation in another. I believe in states rights and all...but some of the junk is plain nutty. Basic Constitutional rights should apply to all equally across all states. | ||
| Ourdee |
I too believe in the State until the State violates a man's rights. | ||
| Ratbuell |
I think state law should REINFORCE federal/Constitutional law...but not contradict it. See: "gun free zones"; requiring permits to purchase and/or carry (background checks I can understand to a point, to keep guns away from felons); red flag laws; "sanctuary" locales (refusal to cooperate with ICE or even make illegals obey the most basic of laws - murder, rape, home invasion)...areas who cross those lines should lose ALL federal funding until such time as those rules are removed, and restored to Constitutional adherence. Saw this in a hotel lobby today, when leaving a training class for work - this is an online version, I saw the AP print version in a newspaper: https://news.yahoo.com/gun-sales-expected-climb-ho liday-200425909.html I know once my finances are straightened out and the house sells....I'll be adding to my collection. | ||
| Gregtonn |
 G | ||
| Gregtonn |
https://www.bearcreekarsenal.com/bca-ar-15-complet e-upper-assembly-350-legend-16-chrome-moly-vanadiu m-parkerized-m4-contour-barrel-carbine-length-gas- system-1-16-twist-w-15-mlok At this price it's hard to resist and it gets good reviews. https://www.youtube.com/watch?v=NCwfONJEcNE Sorry for all misinformation earlier, massive brain-fart day. G |
