AccuMax bullets………..
Recently Kyle contacted me and asked if I would test some new bullets he was going to offer…………As in “start his own bullet company!” Of course I agreed and he subsequently sent me a Styrofoam box with individually separated beautiful looking 275 gr. bullets with needle point aluminum tips just oozing with precision! I knew for a fact that both he Jeff and Bill had been shooting the various Parker 275’s with a single powder charge of IMR 4198. I also know it is common knowledge that they along with many on the forum are getting excellent results with 78 gr. of that powder when shot in heavy barreled bolt action .45’s with custom barrels……….NOT the thin factory barrel converted “break opens!”. I, on the other hand have generally been a proponent of duplex loads but since that formula had been working well I agreed to test them with said load. Kyle did ask me to do an honest evaluation which I said I would do. He also asked that I not post anything until after he got his web site up and running around the first of the year.
So, on 12/28/15 I headed to the range with a supply of IMR-4198 loaded in 78 gr. vials. Kyle did mention that his gun likes to shoot them on a fouled barrel………..mine was J-B clean so I needed to get some fouling in it prior to testing. Since I already had another test in mind prior to getting these bullets, I used the fouling process to test the new, (to me) booster powder; this being “Unique!”. I had been loading some .380 auto cartridges with Unique and in looking at it and its position on the burn rate chart (a flake powder just like Clays but slower; yet not as slow as Blue Dot). So first off, I just fired three shots with a duplex left from last week. Then shot a group with 10/60 Clays/H-4198 and 10/60 Unique/H-4198. I think with more testing exclusively with the Unique, it definitely could be a viable booster. I know some have problems finding Clays and RD but Unique is a pretty popular pistol powder. Again, when switching powders, it is really necessary to get a few shots down the bore before doing serious testing ……….and you can see the first shot was out of the group (so to speak).
I now had eleven shots down the bore but wanted to ease into the straight IMR-4198 and did so with 74 gr. and a 300 gr. XTP……….here again, the first shot was out of the group! Now, I did an adjustment on my NF 8-32 scope by putting two 275 Ballistic Extreme’s with 78 gr. of IMR-4198 down range. A total of 18 shots with the last five being straight IMR-4198.
Mind you, this is an honest test with both poor and good results. The weather was perfect: 65 degrees cloudy, almost but not raining with ZERO wind. My gun is a Rem. ML action with 28” Brux 1 – 20 heavy varmint taper barrel with a Harrell’s radial muzzle brake. Ignition is via Luke’s plug with a .028” pure carbide bushing with standard 5/32” flame channel. The barreled action is pillar bedded in a Boyd’s ProVarmint stock with a Shilen 2 oz. BR trigger. The gun sets in a much modified lead sled which is allowed to smoothly recoil in a special base. A 16 lb. lead bag of shot sits on the sled. When recoiling, there is total weight of 52 lbs and the gun slides back about one inch. When the crosshairs get set on the 1/8 dot or similar POA it is rock solid and with the 2 oz. trigger there is virtually no “pulling” of the trigger. I have tried to get most of the human factor out of the shooting process so the load and bullet can get properly evaluated.
OK, so going to target #5 shots one and two are cutting in the same hole……….great! Then shot #3 moves 1 ½” left and ½” low giving me a 1.6” group?
WTF?................Do some waiting and cussing before going for the next three shot group.
Target #6…..shot #1 goes right where 1 and 2 did on the first group……….but then two goes an inch high and to the right??? Shot #3 goes right back in and cuts shot #1 for a 1.6” group?
??
Target #7………..shot #1 goes right where it should but then #2 3 ½” right and 1 ½” low?..........#3 comes back up but still 2” to the right of shot 1 for a 3.8” group………This time a big WTF?
Of the nine shot fired, five of them would have made a pretty 5 shot group? So what happened to the other four? All powder charges weighted just like I do on my CF match loads…………I did not use the powder measure for these as I usually do. While the velocities of all three groups were very similar (2967, 2957 and 2961), they all had fairly large Extreme Spreads (42, 41 and 39). Scratching my head as to what the problem might be, I decide to try some 74 gr. charges I have loaded, thinking maybe they are being driven too hard?
So on to group #8 at 74 gr. of IMR-4198. The velocity decreased to 2853 and the ES jumped to 69 fps and the group at 2.5”. Now I am really getting frustrated so I decide to try the same 78 gr. IMR-4198 load with a 275 gr. Ballistic Extreme to see what happens?
In comparing the two bullets I noted that the bearing surface on the AccuMax is about .100” shorter than the BE?...............Hmmmmmm?
Going to group #9 you can see the results? A .6” three shot group, the velocity average is 2966 (right in the same ball park as with the AccuMax bullets) but the Extreme Spread is ONLY 8.8 fps! Now my thoughts are running along the line of several factors:
First, the bearing surface is a noticeable difference and maybe giving more stability to the bullet? Two, the Parkers have a .016” wall thickness on the jacket and the AccuMax has .021”……………are the Parkers more easily obturating? Then, the ignition system I am using is different from the “HIS” (Hank’s ignition system) that all the other testers Kyle gave bullets to are using. Kyle also informed me his bushing is .035” while mine is .028”. HIS uses LRMP and mine is using a Winchester 209 standard shotgun primer. Mag. 209’s tend to stick on my bolt face and the CCI’s leak………while Win. 209’s come off clean as a whistle every time (which is now over 1,023 times). So, which of the three might be causing the problem? My friend Bill, who was shooting with me, said: “Why don’t you try one of your duplex loads? You and Herman always do so well with them?” So, in desperation, I decided to try a duplex.
I had had some good results in the past using 4759 under H-4198 with the Parkers and happen to have a box of this configuration on hand. But again, did not want to go straight from IMR-4198 to a different powder without firing a few “foulers!” So, I grabbed some 250 XTP’s and shot three with that load just to condition the barrel (they shot terrible but did what I wanted)
Moving on to target #11, I shot the 275 AccuMax with 10/60----------4759/H-4198. That load put together a five shot .900” group with an average velocity of 2799 and an Extreme Spread only 18 fps.. (Hmmmmmmmm, now we are on to something!) This to me definitely shows that not all powder charges in every gun are created equal? It is just a matter of switching from a straight charge to a duplex (and in this case, any old duplex and for the first time?) made the difference in Night and Day. So Bill says: “If I were you, I would shoot a group out at 300 yards!” Due to impending rain, I had not put up a target but ran (well drove) one out there. Shooting he same load, three shots formed a nice 2.0” triangle! Not too shabby for a first time bullet with a unknown duplex? I was tickled pink to know Kyle’s bullet can really shoot!
In conclusion, I have to say that Kyle did a great job with this new bullet. The fact it did not want to shoot with the load he was using has nothing to do with the quality of the bullet. It is the charge behind it that will make the difference. It appears to be a question of possibly the ignition system used to light the powder, the jacket thickness, the bearing surface along the powder charge. Any of which could be the difference? Due to the relatively small sample (actually very generous at 25 bullets) it gets hard to nail down the reasons for an accuracy issue. My thoughts would be a hotter ignition. Were I to go to a .035 or .040” bushing with a larger flame channel and a Magnum 209 primer, it could solve the problem. On the other hand, using a duplex to get the bullet obturated with a standard 209 is another alternative. I know why Kyle’s jacket is thicker? ……………….and that is to make for a better hunting bullet.
The shorter bearing surface with the bullet weight the same as the BE and MH is what leads to the AccuMaax’s higher BC which is more desirable! I think Kyle has done his homework but with any custom product it may need some fine tuning on the part of the shooter.
…..And Kyle? Thanks for giving me the opportunity to be a part on your new venture.
Richard
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