AR15 Barrel Length vs Velocity - Part 1

everyone today I'm gonna be doing a video that I'm pretty excited about and working on this video for a while tryna can get all the components together and finally today is the day I'm gonna be doing it or at least trying to hopefully everything goes well so today I'm going to be doing as you probably saw from the title of this video a velocity video comparing different barrel lengths in ar-15s across three different bullet weights so I have a seven and a half inch barrel a ten point three and eleven five a fourteen five a sixteen and eighteen and a twenty so I'm covering a lot of really common barrel lengths as well as a wide variety of barrel links again seven barrel lengths from seven and a half all the way up to twenty inches now I know that this is not going to be the most empirical test if I were to do that I'd have one barrel that I just progressively cut shorter and shorter as they go however that's a little unrealistic for me and also this will give you more of a real-world idea of what you can expect now all the barrels I'm going to be shooting today are chambered in either five five six or two to three wild and the ammo I'm shooting today is all going to be from Fiocchi ammo as you guys know Fiocchi has been providing me ammo for a long time which I really appreciate and in my experience it is some of the most consistently loaded factory ammo available on the market you've seen in other video tests I've done just how consistent the velocity is so I'm gonna be shooting at the lightest there are 55 grain full-metal-jacket the middleweight is the 62-grain Full Metal Jacket and their heaviest one that I'm shooting is the 77 grain Sierra match kings that they load up again I'm gonna be shooting all these four velocities so I have a cold well coronagraph down there which will plug into my phone so I can record all the data and get some good averages and everything for you let's see a lot going on here so I'm trying to make sure I mentioned everything you guys have seen me shoot this ammo and stuff before so today we're gonna hopefully get some good quantification of just the velocity we're not shooting for accuracy today we're just trying to get the velocities down and recorded what I'm gonna do now is give you a brief overview of the uppers that I'm going to be using for this if you don't care about that and you just want to skip to the results go the timecode listed down here at the bottom of your screen again if you just want the information but I know people are gonna ask about these uppers so I'm just gonna give you a quick walkthrough of each of the uppers / rifles that I'm going to be shooting today so at the shortest I have this little guy here this is a seven and a half inch upper it's got a fax in firearm seven and a half inch barrel chambered in five five six and then I have a kak flash can on the front of here I did a video dedicated about that barrel so you can look at more into that if you'd like the next barrel I'm gonna be shooting here is a strike industries strike fighter barrel this is their ten point three inch barrel chambered in two to three wild I got a Timber Creek outdoor handguard on here which I'm going to be reviewing soon and then just for right now it's gonna be optics are gonna be going back and forth because I have more uppers and I do optics right now for this test right now it's got a vortex direct fire to on it next up is gonna be this guy this is an eleven and a half inch BCM five five six barrel this is their enhanced lightweight barrel complete BCM upper this is their kmr handguard got a streamlight protac rail one up here arrow precision flip up iron sights primary arms red dot and this is obviously attached to my SBR so I might as well talk about that now I'm going to be shooting across three different lowers corresponding with a different barrel links for these short barrels up to eleven five I'm going to be using my spikes tactical SBR lower here with the strike industries PDW Viper stock I've got reviews on that if you guys are interested so I'm not going to go too much in depth there let's see next one up we have here the spikes tactical 14 v complete upper here it's got the spikes tine a comp up here on the front right now I just have an enforce wml here the new generation ones that I'm doing testing with right now it's got a spikes tactical volt carrier group but I'll probably be swapping that out for this video as I'll talk about here in a moment and then down here is a Aero precision enhanced lower receiver that I built it's got a oh by the way the trigger in that SBR lower is a guys liji 2's trigger the trigger in this lower is the rise armament ra 5:35 and have a Magpul stock back here one of the s SLS's then we have a 16-inch BCM complete upper here this corresponds with my complete bc m rifle but I just took the upper off it for this again cam our handguard this is one of their kind of full profile barrel so not one of their enhanced lightweight ones got a primary arms one to six a CSS up here as well as another wml up here on the front which I believe I have a review on next up 16 18 so we have this 18 inch rifle here this is pretty much completely error precision that I built it's got an 18 inch two to three wild stainless steel barrel it's got a primary arms four to 14 first focal plane DMR HUD scope on it the lower again is err precision and it's got a rise armament or a four three four trigger in this one and this is going to be what I'm using for the rifle length gas systems which then brings us to the last upper which is a 20 inch fax and firearms match series two to three wild barrel it's got a Midwest industries handguard on it Midwest industries upper receiver as well as a Midwest industries optic mount with a vortex Diamondback HP scope in it that's kind of a quick overview of all this stuff I think I caught them all if I remember correctly if not I will make mention of the uppers I'm using as I go so though I'm gonna be doing this test again I have microaggression up I'm gonna run each upper through the 55 green then I'm gonna let them cool like progressively as I go so then after I run everything through 55 grains better run everything through 62 grain and we're gonna run everything through the 77 grain the reason I want to do that is because I'm doing 10 shot strings of fire that chamber is going to be warming up and I don't want the change in barrel temperature and chamber temperature to affect the velocity in the later testing so I'm going to shoot 10 rounds at a time through each upper then move on so that should again keep it as uniform as possible and give us the best data points as possible also just for the sake of testing for another project I'm doing I'm gonna be using this same bolt carrier group through all of them it's one of the new sharps rifle company bolt carrier groups I'm gonna be doing a review on that soon I figured this would be a good chance to get 210 rounds through it really easily and then also get tested through a bunch of different uppers and see how it works so I'm gonna be canned in this across all the uppers and I'll probably have to can optics across one or two of them just to make sure I can safely shoot through my chronograph and not shoot my chronograph so with all that introduction stuff out of the way I'm gonna start shooting these I'll probably roll in some footage but we're just gonna cut to what my results are and you'll see the footage rolled over as we go into each one alright so we just finished the testing and without really looking too deep into it I can already say we got some interesting results so I'm gonna go ahead and do is just read off all the results that I got for the 55 green 62 grain and 77 grain I'm gonna be complying compiling a list I'll either put it on the screen or I'll have a link a link to a place down below probably do it on screen I'm gonna just read off again the results and then we'll do some extrapolations once we're done with that so let's go back to the first load we shot today which was the 55 grant Fiocchi through that seven and a half inch fax and firearms barrel again chamber ten five five six so alright first of all I want to say Mike Mike Caldwell chronograph did exceptionally well I I'm so used to doing it on sunny days where the lighting can be a little spotty I'll get error readings it read every single shot all 210 rounds that we shot today so getting into the results the average for the 75 inch barrel was 2020 1.2 feet per second that's really really slow that's sub ak-47 velocities that's even slower velocities than what I'm getting out of three huh I had a standard deviation 59 and a spread of when he 181 the 10-3 had an average of 2,400 and 12 feet per 24 point sorry twenty four hundred and twelve point eight feet per second with a maximum spread of 178 and a standard deviation of 63 so again pretty big spread there the eleven five we had an average of twenty five 41.8 with a maximum spread of 86 and a standard deviation of 30 point six so again we're rollin lowering that extreme spread let's see if that continues B fourteen five we had twenty six seventy seven point three for the average with an extreme spread of 81 and his standard deviation of twenty nine twenty four point nine so again spread went up a little bit from the eleven five let's see okay 16-inch had a a verge of twenty eight fifty one point one with a maximum spread of 141 and a standard deviation of 37 c 18-inch barrel average of twenty eight thirty seven point three spread of 120 and a standard deviation of thirty five point seven and the 20-inch had an average of twenty eight 87.5 with a spread of 113 and a standard deviation of thirty three point six so some interesting things to note here is that our average velocity for 1612 okay hey sorry let's all save the extrapolation for the end 62-grain 7.5 inch barrel at an average of two thousand and five point five feet per second standard deviation of 39.6 maximum spread of 101 10.3 we had a 23 point sorry 2,350 3.9 average standard deviation of 50 724 and a spread of 205 feet per second [Music] 11/5 we had an average of 2004 54.1 standard deviation of 15 point 7 and a maximum spread of only 54 that's actually a really really impressive spread 14 5 we had 26 60.9 is the average standard deviation of 39.3 spread of 122 16-inch barrel we had an average 28 15.3 seed standard deviation of nineteen point four and another all spread of only 58 two feet per second not too shabby 18 inch we had an average of 2807 point three a maximum spread of 89 and a standard deviation of 29 28 20 inch we had an average of 28 seventy one point one standard deviation of 30 point three in a spread of 96 again probably noticing some interesting things that we're gonna talk about in a second 77 grain obviously gonna be a slower round and would definitely notice that here with the 7.5 inch barrel an average of 1863 point 3 standard deviation of sixty six point nine and a spread of 189 ten point three who had an average twenty one forty five point five standard deviation of 64 point nine and a spread of 193 that was that 10 yeah 11 5 we had an average of twenty to thirty nine point seven standard deviation of forty eight point six with a spread of 124 for the 14.5 we had an average of twenty three eighty seven point two standard deviation of thirty four point five and a spread of 120 16-inch we had an average 25 18.9 standard deviation of 31 and a spread of 108 18 inch we had a velocity average of 25 forty two point three their deviation of forty nine point eight and a maximum spread of 162 and then last but not least we had the 20 inch barrel at twenty five seventy nine feet per second standard deviation for the fifty three point nine in the maximum straight 150 so one of the things you're gonna notice really quick is obviously the shorter the barrel the lower the velocity and in general the longer the barrel the faster the velocity however something interesting that you may have noticed again as I was reading those numbers off is there were situations where the 16-inch average velocity was higher than the average 18-inch velocity now again each of these to do a perfect empirical test I'd be using the same barrel and just cut it down there's obviously going to be slight variations and chamber dimensions which are all going to affect a velocity however overwhelmingly it in my testing whether we're talking 55 green 62 grain or even 77 grain I didn't experience a whole lot of difference between a 16 and a 20 inch barrel again not saying that's gonna be the case all across the board however in my specific cases that was the case which again I find pretty fascinating um we're not talking about accuracy or anything here we're just talking about velocity and I know people are gonna say barrel length has no impact on velocity sure or excuse me barrel like there's no bearing on accuracy sure fine whatever we're just talking about velocity here now obviously our largest jump in velocity also course mounted with our largest jump in barrel length which was the 75 to the 10 3 in the 55 grain we had a jump of almost 400 feet per second in the 50 62-grain we had a jump of almost 350 feet per second and in the 77 s we had a jump of about 300 feet per second that's a pretty significant increase that's all it's over a 10 percent or but like between a 10 and like 20 percent increase in velocity going from a seven point seven point five to it even a ten point three inch barrel and obviously we had jumps up from there what that tells me is that seven point five is not necessarily a great choice for personal protection the terminal ballistics are just not going to be there for those of you who I have experience with five five six the efficacy of five five six comes from the barrel length and the velocity there so that's why the Marines for so long stuck with a 20 inch barrel because they wanted that added velocity to theoretically have better terminal ballistics now people are gonna say well from you know inside your house distances it doesn't matter whatever makes you happy but my point still stands that 75 is not a good option for personal protection because of the lack of velocity corresponding to a lack of performance and as far as terminal ballistics goes now I can make a full more in depth video on that later maybe do some gel tests between say sixteen and a seventy-five or even just that eleven five versus seventy-five just so you can still see in those short barrels how much of a difference there is but again that it's gonna be a topic for another video if there's interest let me know down below if that's something you want to see again I found a fascinating that there wasn't a significant increase from a 16 to a 20 inch barrel again in my case because that like three and a half wet just under three inch jump from seventy five to ten point three correspondent in it you know ten to twenty percent increase in velocity that 4-inch jump from sixteen to twenty again in my case did not have a significant increase in velocity and in one case had a decrease in velocity so again I find that fascinating what my extrapolation is there is that you're getting a more consistent burn rate once you hit that 16 inches so again you probably saw flame and stuff coming from that 11 v and really not much coming from the 16 through that 20 inch barrel just because all that powder has that chance to burn before it leaves the barrel and part of that also is going to correspond to our average velocity the average velocity seemed to be the best around that 14 5 to 16 inch range right in there and part of that is probably going to be the barrels that I'm shooting him through seem to be very consistent but also you're getting a more consistent burn rate that doesn't necessarily explain why I had some some wider spreads in the 20 inch area but if in my opinion would explain some of that difference in the shorter barrel lengths but again the fact that it's on both ends kind of I don't know you can judge that hypothesis how you will see is the hypothesis definitely not a theory yet overall I again I found I find these results fascinating I know that they're gonna be people who say well now test three in a blackout no test 308 test whatever if you provide me the barrels then I would be more than happy to however it took a long time just to get this many barrels and uppers to be able to do this test a pretty significant financial investment for me to be able to do this video now I did have some support again Fiocchi did provide the ammo for this test spikes tactical provided that 14 5-inch upper for me to use and I'm gonna be doing a full review on that later you know I had a lot of company support you know Midwest and it helped me with the parts to assemble this upper arrow precision helped with building the 18 inch upper and that that carbine lower that I was using straik industries as well primary arms for I think one of the scopes is one that they provided for for testing the other ones I got myself so I really appreciate all the companies I've been willing to help me out for that and again if we do want to do different caliber testing in the future and we can definitely do that now I know something else that people are gonna say is man these velocities are really slow for that that grain a bullet if you should test this one because you know the the m855 or the m193 is supposed to be this velocity I wasn't necessarily testing the velocity of you know this 55 grain or 62-grain versus other 55 or 60 2 grains I simply was just testing velocity against each other in different barrel lengths and I wanted to do a variety of bullet weights just to again give us as much data as possible again well I have all that data listed on the screen as we were talking about it so you can sit down copy that down if you want extrapolate however you want from that but again I found these results interesting and I'm definitely anxious to see your guys's thoughts on the testing we did today just as a side note if you like this video and you want to see others like it go ahead and subscribe to my channel I just got the invitation to start uploading to full30 today so I'm gonna start doing that this video will probably be one of the first one I upload two full 30 so if you're watching this video there I really appreciate you coming for 30 and supporting videos here I've also started uploading to some other sites so you know wherever you're seeing this I guess thank you for for coming and finding this video I do have a patreon page so if you guys are interested in that and you feel so inclined to go and check that out all my videos get posted early there as well as some patron exclusives get posted there so I and I really appreciate the support I'm getting there it helps purchase ammo and help compile parts to be able to do videos like this one I really appreciate the support I'm getting over there and again for those of you who want to check that out links will be below if you have any questions comments or concerns going throw those in the comment section down below I'll try to get back to you as quick as I can so with that the range is getting a lot louder so I might as well wrap this video up now and I'll go ahead and say as always I hope you're able to get something out of this video and I really appreciate you watching I think those birds are having an orgy okar to them I'm not one to judge

Channel: OreGear

Views: 78,399

Rating: 4.9216042 out of 5

Keywords: ar15, barrel, length, velocity, ballistics, terminal, external, speed, bullet, 55, 62, 77, smk, m855, m193, mk262, bcm, bravo company, aero precision, strike industries, midwest industries, 7.5, 10.3, 11.5, 14.5, 16, 18, 20, m4, m16, rifle, pistol, carbine, mid length, spikes tacitcal, fiocchi, fiocchi ammo, chronograph, chrono, test, science, overview, trial, comparison, oregear

Id: _mAA0PLrNco

Length: 20min 41sec (1241 seconds)

Published: Fri Apr 06 2018