SBR Myths and Misconceptions

everybody aren't counting sage dynamics in this video we're going to take a look at some common myths or misconceptions when it comes to short-barreled rifles I am a fan of the short barreled AR platform but I do recognize that there can be some potential trade-offs one thing that you see come up every now and then is you generally there's two topics of discussion that come up when we talk about short-barreled rifles now for the AR platform arguably originally designed for a certain barrel length 20 inch 18 inch 16 inch 14 5 what is the optimal barrel length well the round really does perform better out of longer than shorter barrels but that doesn't mean that you can't get acceptable performance or reasonable or good performance out of a short shorter barreled platform however based on the characteristics of what we want rifle rounds to do and how they're the most effective we do have to pay special close attention to not only the round that we're using but the barrel length that we're using it out of generally to get the favorable ballistic terminal ballistic capabilities out of a round I need to be able to hit a certain feet per second out of whatever my barrel length is going to be arguably between 24 and 2500 feet per second based on the round and the characteristics of the round there aren't a whole lot of guns out there capable or actually I don't know too many guns at all capable of twenty-four twenty-five hundred feet per second in the 7.5 inch length which is why I don't choose or I don't own any guns that short I generally will not I should say I will not go shorter than 10 inches 10 inches is the the minimum length that I'm willing to accept for a self-defense or a duty rifle in the AR platform 12.5 is a good length 14.5 is what that what you see the most in the military law enforcement you see between 10 and 14 those are shorter than what the round was intended to be fired from you know 18 20 even 20 to 24 inch guns so am I still getting good performance out of the shorter barrels to make it worth it what do I gain with a shorter barrel the biggest answer to that question is maneuverability concealability makes the rifle a little bit more versatile for a wide range of applications versus it just being a dedicated long-range SPR type platform so you see law enforcement for SWAT purposes and or CQB whatever you want to call it the shorter guns just maneuver better sure I mean there's probably probably people watching this video right now that your grandfather great-grandfather you know he cleared houses in France using a garand it doesn't mean you can't do it it's just not something that's recommended for versatility maneuverability the shorter guns are gonna get the job done but do is the ballistics still going to be there we're gonna look at the ballistics in two aspects we're gonna look at accuracy and then we're going to look at terminal ballistics using ballistic gel for the purpose of this video I'll be using two different SPRs I'll be using an S MOS upper and ten inches with a one-in-seven twist two to three wild chamber and I'll also be using a primary weapon systems mark 1 1/2 which is a 12 inch 12 point 8 5 inch barrel and at the same chamber 2 to 3 wild but this gun will be in a 1 & 8 twist this isn't a comparison between the two guns necessarily of course because the chambers or the twist rates are different but it is a look at two different SBR two different common SBR lengths now there's some people produce 1111 5 11 8 5 seen 10 - I've seen 10 5 10 85 there are a bunch of different lengths available in each inch category but the most common ones you see 10 12 14 5 so I wanted to offer a 10-inch gun and something just 2 inches and change longer to show the difference between the two once we get the sermon on ballistics but as far as accuracy goes accuracy is an easy thing to demonstrate for the purpose of this video I'll be using the same round in both guns the entire time I'll be using the Black Hills 77 grain otm you might also know it as the mark 2 6 - it's a great round as a highly accurate round it is my go-to round for proving accuracy on a platform so to get the accuracy myth out of the way first up is my SMOS I'm firing that 77 grain ocm we're shooting out at the zero distance of 100 yards [Applause] and here is the primary weapon systems mark 1 1 2 mod 1 shooting same distance 100 yards so if you're doing your mental measuring math at home you can see that both guns are within a 1 MOA sub one my not counting for fliers accuracy is not an issue I shoot both of these guns regularly at the 3 400 meters now the envelope for the round out of that gun you are gonna lose you're starting off with less muzzle velocity so it's you're not going to get the same kinetic energy at distance that you would get out of say a 14 or 16 or 18 inch and I don't think anybody's debating that but what it what kind of muzzle velocity are we seeing out of these two guns well here's a look at the SMOS same around 77 grain black hills OTO and here is the primary weapon systems mark 1 1 2 mod 1 check taking a look at that muzzle velocity so the muzzle velocity is close to in the neighborhood of acceptable muzzle velocity for ideal terminal ballistics out of that round or out of the 2 to 3 / 5 5 6 around in general now when we start looking at ballistic gel we're looking for two things we're looking at penetration and fragmentation having both is ideal for the rifle based on the wounding characteristics of the rifle round there's a wealth of information out there if we want to get into the minutiae and the very specifics of ballistics and if you choose to use a 2 2 3 5 5 6 platform for duty or for home defense I highly recommend that you have a really good understanding of what you're looking for in ideal performance but just as a brief overview I'm going to get a permanent wound cavorite cavity I'm gonna get a temporary wound cavity temporary wound cavity is going to be created by the velocity of the round the lossy of the round the light of the round sometimes causes more fragmentation but I'm looking for fragmentation as well as a secondary the biggest wounding properties of the rifle round itself is going to be that temporary wound cavity which can be two to three times larger on expansion than what you're gonna see with the permanent cavity even if the round happens to fragment tumble yah pitch all these things that bullets can do when striking ballistic media or real-life human beings now for ballistic testing I'm using 10 percent calibrated ballistic gel from clear ballistics 10% is considered to be pretty much the testing standard to simulate human tissue it does not simulate things like bone or or other media that should encounter inside the body it's just simulating muscle mass tissue fat things of that nature ideal penetration is is something that comes up often people want to know why why do you want 12 or 18 inches of ideal penetration well think about the concept that that we're not a to simulate bone inside the ballistic gel so that extra distance penetration distance is something that's factors into that and another factor is where is the round fired from in relation to the human form remember people are three-dimensional even though a lot of us spend our time to shoot in 2d paper if you consider a shot fired from from different angles different angles mean more travel to reach critical areas of the body so if a round was fired from say on your back into a standing threat the round is going to have to travel further to get to that high thoracic package depending on where it enters so that's also factored into the science of terminal ballistics when it comes to checking how well rounds perform now be shooting both rifles at four distances I'm going to do 10 yards 25 yards 50 yards and finally a hundred yards on both guns showing you the ballistic gel and then the extracted rounds as they fragment it so without further ado let's get started at the 10-yard mark with the SMOS that first shot was shot was actually surprising to me while we did get 19 inches of penetration we had very poor fragmentation at 10 yards out of that 10 inch gun one in seven to us two to three wild chambers firing the the 77 granny o2 in Black Hills let's see if the PWS fared any better here's the PWS mark 1 1 to mod 1 at the same distance 10 yards you we only got 18 inches of penetration as far as I can tell sometimes those micro fragments you miss them in the jail or they exit the jail body and you don't know where they went so you can't measure but that penetration distance and we had some pretty good fragmentation and some spiraling of the actual fragments themselves so that would have been a really good wound channel based on that distance on that barrel length next up we're moving on to 25 yards here's the SMAS 10 inch upper we had 16 inches of penetration with very wide fragmentation and a good permanent wound channel I was very impressed even though I didn't get 18 inches of penetration I got 16 inches with very very solid fragmentation which is a pretty good trade-off considering what I'm wanting the round to do now let's see how the PWS mark 1 1 2 mod 1 fares at 25 yards 22 inches of penetration with very wide fragmentation in the 10% calibrated ballistic gel you can see these guns are close to each other in length but they do have a different twist rate and that definitely factors into some of the performance discrepancies between the two the between the two guns because as you can see barrel length and twist rate are definitely a factor the one-in-seven is very very lends itself very very well to the 1 into 1 and 7 barrel is 77 grain one-in-seven barrel is a match made in heaven according to some people I prefer to shoot the 77 grain I won't go over 1 and 8 I don't own any 109 guns 109 the 77 probably wouldn't stabilize very well from from everything I've heard I've never personally tried it myself but I've never been a fan of the 109 because you're just so limited in what grounds you can use it here is the SMS at 50 yards 77 GRA noti'm you nineteen inches of penetration with again wide fragmentation it seems like once we got past ten yards the rounds started performing as they should we're getting good fragmentation good permanent wound cavities and good penetration distances and that's definitely what we want now we're out 250 consider the distance that we're at right now 50 yards for a lot of people that's going to be well within their reasonable self defense envelope for the use of an AR platform and not in sight in a home defense situation you're probably already beyond the maximum distance that you are able to shoot inside your home for a self defense type setting so for and I can't say definitively that you'd never have to take a shot farther than that but once we get past 50 we get into PID issues can you actually see and positively identify what you're shooting at to begin with just being able to see a person isn't necessarily enough to be able to say okay I'm going to go ahead and shoot at this distance so at the 50 yard mark that 10 inch gun is still doing pretty well now let's take a look the primary weapon system is mark one one two at the same distance you only 15 inches of penetration with decent fragmentation so there's there's definitely some performance inconsistencies that are now really setting themselves apart between the two barrel lengths between the two twist rates ideally what I would like to have done is is compared to identical guns with just slightly different barrel lengths when they will do that but again it's not a comparison it's just showing you how to different SPRs are performing under the same conditions a hundred yards is is ballistically speaking a pretty long way for terminal ballistics there have been plenty of people who pointed the fact that the military's chosen round or or the later variations of the chose around the m855 na v a1 loses its fragmentation capability around eighty meters I can't verify that that's just something that I've seen people that I would trust the knowledge from saying that and they're in their own videos and their own articles on fragmentation and terminal ballistics out of that round now the 77 grain otm from Black Hills is it's it's one of the better rounds from people who know use in designate marksman rifles and for sniper applications during the war in Iraq war in Afghanistan it was a round that was really good for urban use more for Iraq and Afghanistan in that case and I can't speak too great on that because I didn't use that round and in that capacity and either of those countries so I don't have any first-hand experience but I know from guys that did say it performed really really well at your intermediate distances and I consider to be a hundred yards and in or a hundred meters and in to be those intermediate distances at which you'd expect to need that great precision that the 77 grain can provide but still going to give you good terminal ballistics so without further ado here's our SMS ten inch at 100 yards you 23 inches of penetration but as far as I can tell zero fragmentation the round was deformed the oh guy I've had to kind of come off just a little bit was still hanging on like a hangnail and the round had almost completely rotated 360 degrees a face back towards the entry wound the wound cavity has a lot of pitch and yaw to it so that round definitely did the the ubiquitous tumble that some people like to talk about the round doing I would have still preferred some fragmentation but at a hundred yards out of a 10 inch gun I'm still getting some favorable ballistic capabilities out of it basically it performed like a pistol round might at that hundred meter disc or a hundred yard distance now let's see how the 12-inch PWS mark 1 1 2 did nineteen inches of penetration with excellent fragmentation there's some good spiraling in there good permanent wound cavity so between the two guns the one that the one consistent performer that we can look at is the primary weapon systems or I should say barrel lengths the 12 inch gun which was for this purpose the primary weapon systems work 1-1 to mod one well so what have we learned 10 inches is the absolute shortest that I would ever be willing to go on the 2 2 3 5 5 6 round now I'm not done with this topic this is just kind of a primer video we just fired on ballistic gel with we didn't simulate or introduce any intermediate barriers or clothing and we only tested one round so look forward to further ballistic videos being done on SPR characteristics on ballistic gel and just performance in general I may get some I may do some round specific because there are rounds out there is quite a few these days that say these are specifically for ideal ballistic terminal ballistic performance in SBR so maybe I'll pick up a couple hundred rounds of those and see how they do in ballistic gel and of course I'm not the only one doing this kind of testing so you know don't just take my word for it there's a lot of other guys out there that do videos on ballistic performances out of barrel lengths rounds and all the things that factored into that but I wanted to put this video together just so I have my little touchstone that I can point people to when it comes to the two of the most common things that I hear when it comes to SP ARS is they're not going to be accurate or they don't have stopping power stopping power is not a real thing that's just a term that was made up to sell mo what your ass actually trying to say is terminal ballistics because around itself based on its own properties can't actually stop anyone at least out of small-arms and thus we start to get into anti material and anti-aircraft rounds you're looking for the ballistic performance on target terminal ballistics we're looking for permanent temporary wound cavity penetration and fragmentation crush cavity if you will so that's just kind of step one when it comes to comparing those things in the future like I said I'll be doing more testing probably on these exact same two guns and with different ammunition but for those of you who didn't know or are just getting into the topic I hope this provides you with some information that help you make a more informed purchase when you're deciding on your SBR or your pistol length that you're going to use for home defense or for duty I'm Erin countless age 9 Amex trained accordingly you

Channel: SageDynamics

Views: 229,198

Rating: 4.9017015 out of 5

Keywords: Black hills 77gr otm, Primary Weapon Systems, sage dynamics

Id: eqk2ZjTnoEo

Length: 19min 3sec (1143 seconds)

Published: Tue Mar 27 2018