kkina
11-12-2006, 11:00
Timlt, this is a reply to your question:
Kevin, given that you're about to come out with the Accustrut, I wondered if you might advise me on a situation I've got. As you know, because you've seen my other thread on my accurized Mini, I've had some really nice Gundoc mods (trigger, bedding, barrel cut/crown, plus compensator), and I have the Ultimak rail. The gun CAN shoot 1" groups and when it's warmed up, I can USUALLY hit pretty close to what I'm aiming at. Considering where the gun started, it's shooting better than twice as good as it did straight from the factory, which is over a 2" improvement in grouping capability, plus it's just more consistent overall. In general, I'm very happy with the gun, even thrilled when it's shooting at it's best. Certainly I feel I got a lot of value from the mods that were done, and they were worth it.
Still, I can't help feeling that there's something missing, still some additional work I could do to address this final issue, now that all other accuracy issues have been well covered. I don't think cryo treatment is likely to help, because I don't have a big problem with vertical stringing. But what I do have is, the first few shots out of the cold barrel are almost incredibly wild. The point-of-impact (POI) of my very first shot can be 18" from my point-of-aim (POA). And even at points during my shooting sessions if I wait awhile for the barrel to cool--and this is especially pronounced now that it's colder outside--when I shoot again the first shot flyer returns, though not as extreme as the VERY first cold shot of each range session. And the problem is, this makes it very hard for me to shoot CONSISTENTLY well, though I can manage to shoot multiple good groups in any one range session, the shooting is just incredibly inconsistent. I'll have 2 great groups, than a horrid one, then 3 good groups, a mediocre one, and 2 horrid ones. It's all over the map, and this is what I want to get under control. And I don't think it's me, in this case. Sometimes you hear people say, this gun can shoot better than I can (meaning that they are the limiting factor in the gun's accuracy). Well that's true with my other rifles (Browning A-bolt, CZ American .17 HMR, Ruger 10/22 with bull A&B target barrel, and I expect the same with my forthcoming Rock River AR15). With each of these guns, they shoot such tight groups, that when I don't shoot as well as I want, in nearly every case it's because I twitch, shank a shot, or otherwise do something to mess up. But usually the resulting poor shots are just slightly out of group, they're not wild flyers that land anywhere from 3" to 15" off in any direction, like the Mini does. And when I shoot the same ammo in my Abolt as in my Mini, I have nothing like these problems with flyers, so again, I don't think it's me. I realize that one can get some flyers just due to using inexpensive Federal American Eagle ammo, but really, there shouldn't be this many flyers. And if that were an issue, I should see the same number of flyers in my Abolt, but I don't. Yet in the Mini, even when I use a quality match-level ammo like Black Hills (the red box stuff, not the remanufactured stuff), I still get the same "frequent flyers" behavior. So I KNOW it's something in the rifle that causes these intermittent hiccups when it shoots. At least, given the evidence I've presented, I think it's the most likely conclusion that it's not me and it's not the ammo, so that leaves the rifle.
Now I know you're not a gunsmith, but I'm curious if you think the Accustrut has any chance of helping me with this problem at all. Do you think further stabilization of the barrel is likely to help keep it from moving around so MUCH when the temperature changes? I expect it will always have some degree of difference between POI and POA when the temp changes, that happens with any gun and is just more pronounced in the current Mini's. But I'd sure like to REDUCE that behavior, so it's not so dramatic, and so I can have a little more reliable first shots in situations where my first shot might need to count. I would be well satisfied if an Accustrut could just bring that down so that the first cold shot is never more than 3" to 5" out of whack with my POA, and thereafter, most flyers are no worse than 2" or 3" off from POA.
I know you cannot make guarantees, and it's my risk if I buy, but do you think given the problem I've described, and the things already done to my rifle, the Accustrut would have a reasonably good chance of making any kind of improvement? Or do you think it would probably only make a marginal improvement at best, and that I should therefore keep looking for mods that might help with the flyers?
I know exactly what you're talking about. Even after extensive accurizing of my gun, including use of the Accu-strut, I get a shifting POI that does not seem to be indicative of the gun's inherent accuracy. I get very small groups, usually sub-MOA for 3 and 4-shot groups, but they seem distributed over a 3 inch area. It does not seem related to ammo, as I get the same results with Fed AE as well as Black Hills and Federal Gold Match for that matter.
This is something I'm currently in the process of studying. Right now I'm looking into bedding of the gasblock, something that hasn't been tried much in the past. It's too early to tell if this will work. I'm trying to come up with a forend pressure-bedding procedure, which is a common solution for thin-barreled bolt-action rifles.
I've got a few other theories, such as uneven slamming of the op-rod cylinder. Maybe the barrel is warping in direct relation to temperature, though not bad enough to cause actual stringing, but enough to change POI. I've even begun to wonder if all the ammo manufacturers have slipped in quality due to the worldwide ammo shortage! I'll post results as I find them.
I don't believe the Accu-strut will eliminate this problem, though it could reduce it. My flyers are only about 1.5" from POA, yours seem much larger. I also get cold barrel shift, mine are about 3 inches for the first 2 shots. I'd suggest cryoing anyway, for $35 it can't hurt, and it might help. Will keep you posted on my studies.
Kevin, given that you're about to come out with the Accustrut, I wondered if you might advise me on a situation I've got. As you know, because you've seen my other thread on my accurized Mini, I've had some really nice Gundoc mods (trigger, bedding, barrel cut/crown, plus compensator), and I have the Ultimak rail. The gun CAN shoot 1" groups and when it's warmed up, I can USUALLY hit pretty close to what I'm aiming at. Considering where the gun started, it's shooting better than twice as good as it did straight from the factory, which is over a 2" improvement in grouping capability, plus it's just more consistent overall. In general, I'm very happy with the gun, even thrilled when it's shooting at it's best. Certainly I feel I got a lot of value from the mods that were done, and they were worth it.
Still, I can't help feeling that there's something missing, still some additional work I could do to address this final issue, now that all other accuracy issues have been well covered. I don't think cryo treatment is likely to help, because I don't have a big problem with vertical stringing. But what I do have is, the first few shots out of the cold barrel are almost incredibly wild. The point-of-impact (POI) of my very first shot can be 18" from my point-of-aim (POA). And even at points during my shooting sessions if I wait awhile for the barrel to cool--and this is especially pronounced now that it's colder outside--when I shoot again the first shot flyer returns, though not as extreme as the VERY first cold shot of each range session. And the problem is, this makes it very hard for me to shoot CONSISTENTLY well, though I can manage to shoot multiple good groups in any one range session, the shooting is just incredibly inconsistent. I'll have 2 great groups, than a horrid one, then 3 good groups, a mediocre one, and 2 horrid ones. It's all over the map, and this is what I want to get under control. And I don't think it's me, in this case. Sometimes you hear people say, this gun can shoot better than I can (meaning that they are the limiting factor in the gun's accuracy). Well that's true with my other rifles (Browning A-bolt, CZ American .17 HMR, Ruger 10/22 with bull A&B target barrel, and I expect the same with my forthcoming Rock River AR15). With each of these guns, they shoot such tight groups, that when I don't shoot as well as I want, in nearly every case it's because I twitch, shank a shot, or otherwise do something to mess up. But usually the resulting poor shots are just slightly out of group, they're not wild flyers that land anywhere from 3" to 15" off in any direction, like the Mini does. And when I shoot the same ammo in my Abolt as in my Mini, I have nothing like these problems with flyers, so again, I don't think it's me. I realize that one can get some flyers just due to using inexpensive Federal American Eagle ammo, but really, there shouldn't be this many flyers. And if that were an issue, I should see the same number of flyers in my Abolt, but I don't. Yet in the Mini, even when I use a quality match-level ammo like Black Hills (the red box stuff, not the remanufactured stuff), I still get the same "frequent flyers" behavior. So I KNOW it's something in the rifle that causes these intermittent hiccups when it shoots. At least, given the evidence I've presented, I think it's the most likely conclusion that it's not me and it's not the ammo, so that leaves the rifle.
Now I know you're not a gunsmith, but I'm curious if you think the Accustrut has any chance of helping me with this problem at all. Do you think further stabilization of the barrel is likely to help keep it from moving around so MUCH when the temperature changes? I expect it will always have some degree of difference between POI and POA when the temp changes, that happens with any gun and is just more pronounced in the current Mini's. But I'd sure like to REDUCE that behavior, so it's not so dramatic, and so I can have a little more reliable first shots in situations where my first shot might need to count. I would be well satisfied if an Accustrut could just bring that down so that the first cold shot is never more than 3" to 5" out of whack with my POA, and thereafter, most flyers are no worse than 2" or 3" off from POA.
I know you cannot make guarantees, and it's my risk if I buy, but do you think given the problem I've described, and the things already done to my rifle, the Accustrut would have a reasonably good chance of making any kind of improvement? Or do you think it would probably only make a marginal improvement at best, and that I should therefore keep looking for mods that might help with the flyers?
I know exactly what you're talking about. Even after extensive accurizing of my gun, including use of the Accu-strut, I get a shifting POI that does not seem to be indicative of the gun's inherent accuracy. I get very small groups, usually sub-MOA for 3 and 4-shot groups, but they seem distributed over a 3 inch area. It does not seem related to ammo, as I get the same results with Fed AE as well as Black Hills and Federal Gold Match for that matter.
This is something I'm currently in the process of studying. Right now I'm looking into bedding of the gasblock, something that hasn't been tried much in the past. It's too early to tell if this will work. I'm trying to come up with a forend pressure-bedding procedure, which is a common solution for thin-barreled bolt-action rifles.
I've got a few other theories, such as uneven slamming of the op-rod cylinder. Maybe the barrel is warping in direct relation to temperature, though not bad enough to cause actual stringing, but enough to change POI. I've even begun to wonder if all the ammo manufacturers have slipped in quality due to the worldwide ammo shortage! I'll post results as I find them.
I don't believe the Accu-strut will eliminate this problem, though it could reduce it. My flyers are only about 1.5" from POA, yours seem much larger. I also get cold barrel shift, mine are about 3 inches for the first 2 shots. I'd suggest cryoing anyway, for $35 it can't hurt, and it might help. Will keep you posted on my studies.