Posts: 232
Threads: 17
Joined: Feb 2017
Well folks, I have gotten more good info from my 24'' sanders upper AR build today, again AR Comp 120gn SMK, that performed really well from my 18'' BCA upper works just as good from my 24'' barrel, this combo has givin me the best accuracy I have seen from these 2 different manufactures, but I will say there's not enough difference between the 18 and 24'' barrels to warrant using a 24'' barrel over an 18'' barrel, My last range trip I shot a 1.25'' group at 205yds from my 18'' BCA in a 20mph wind, today I shot a 7/8'' group at the same distance with 1 shot opening up the group to 2'', very impressive for me, 
Posts: 1,009
Threads: 80
Joined: May 2020
Group size isn't a fair comparison for barrel length. What was the velocity difference between the 2?
Posts: 232
Threads: 17
Joined: Feb 2017
My 18'' 27.1gn 2495 AVE, the 24'' 27.1gn 2540 AVE, my 18'' 27.4gns 2505 AVE, all of these loads had an ES of less than 21. and the SD's in the 7"s. the 18'' I used Starline Brass, the 24'' yesterday I used Hornady Brass, all the Brass I have used in these 2 tests using AR Comp and the 120gn SMK's were new unfired cases, I prepped them as usual then loaded them, as said these are to date my best loads ever from my Grendel's, I'm not trying to run max loads even tho I'm pretty close to it now IMO, with this powder, I'm happy with the results, I also tried A2460 @27.1 and 27.4gns with Hornady brass and 123 and 120ELDM's both shot 4'' groups or worse!!!! from the 24'' tube, same distance, I'm going to give the ELDM's 1 last chance with AR Comp, I have not tried this combo yet from either of my rifles, if they don't shoot, I'll have a bunch of them for sale!!!! 
Posts: 3,340
Threads: 46
Joined: Mar 2011
Mark611 Wrote:My 18'' 27.1gn 2495 AVE, the 24'' 27.1gn 2540 AVE, my 18'' 27.4gns 2505 AVE, all of these loads had an ES of less than 21. and the SD's in the 7"s. the 18'' I used Starline Brass, the 24'' yesterday I used Hornady Brass, all the Brass I have used in these 2 tests using AR Comp and the 120gn SMK's were new unfired cases, I prepped them as usual then loaded them, as said these are to date my best loads ever from my Grendel's, I'm not trying to run max loads even tho I'm pretty close to it now IMO, with this powder, I'm happy with the results, I also tried A2460 @27.1 and 27.4gns with Hornady brass and 123 and 120ELDM's both shot 4'' groups or worse!!!! from the 24'' tube, same distance, I'm going to give the ELDM's 1 last chance with AR Comp, I have not tried this combo yet from either of my rifles, if they don't shoot, I'll have a bunch of them for sale!!!!
Mk611:
I have said it many times on this forum. If your barrel won't shoot 120 SMKs very, very, well with any standard load for the Grendel, or .260, or 6.5 CM, et. al., then you need to get a new barrel.
They are not a high speed ULD or VLD but that is what makes them super tolerant to things like powders and charges, seating depth, throat types and lengths, twist, etc. Tangent ogive bullets tend to give these advantages but the 120 Match King not only has these features but is also a very good overall length for a short case like a Grendel.
With the 120 Match King you are almost guaranteed to find a sub minute load on your first try. Go to the Secant ogives and no matter what you do, you may not find a decent load. If you do find one, I bet it will have taken a while and you won't be able to vary from it without having problems.
LR-55
Posts: 232
Threads: 17
Joined: Feb 2017
03-06-2023, 08:29 PM
(This post was last modified: 03-06-2023, 08:36 PM by Mark611.)
LR-55, I know you have made a lot of comments about using the 120gn SMK's, on my other posts and other posts I have read, your input has had a great value to me, I remember you saying these are basic bullets of its bigger brothers, in 308win, and my custom built 308win loves the 175gn SMK's, these 120gn 6.5mm bullets give me the same accuracy as my 308, on a good day I can put 5 175gn SMK's inside your thumb nail @200m, <img src="https://i.ibb.co/LdT1gng/3405.jpg" alt="3405" border="0" /> I can not get it to show the pix!!!
Posts: 3,340
Threads: 46
Joined: Mar 2011
Mark611 Wrote:LR-55, I know you have made a lot of comments about using the 120gn SMK's, on my other posts and other posts I have read, your input has had a great value to me, I remember you saying these are basic bullets of its bigger brothers, in 308win, and my custom built 308win loves the 175gn SMK's, these 120gn 6.5mm bullets give me the same accuracy as my 308, on a good day I can put 5 175gn SMK's inside your thumb nail @200m, <img src="https://i.ibb.co/LdT1gng/3405.jpg" alt="3405" border="0" /> I can not get it to show the pix!!!
Mk611:
I liken them to the 168 Match King. They appear to be proportionally the same although I am pretty sure there is a difference somewhere.
When the 175 Match Kings came out, the 168's were rendered obsolete.
Like the 120 Match King though, I would say the same for the 168. If a .308 won't shoot a 168 Match King under a minute without much effort, a guy may want to get a new barrel. That bullet is almost foolproof.
Both are fantastic at 300, difficult at 600 if there are winds, and useless at 800 - 1000.
However, the Grendel's 30 grain case capacity really limits its velocity so that 120 is a real workhorse of a bullet to the ranges where a guy doesn't have to roll the dice if there are winds.
LR-55
Posts: 232
Threads: 17
Joined: Feb 2017
|
