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Post by rexxer on Feb 27, 2009 10:33:39 GMT -5
I'm working on a couple projects and was wondering what tolerance between the bore and the bullet sabotless would yield the best results. I think Harley has a .448 bore and has had great results with a .451-.452 knurl. So his rifle seems to like a .003-.004 press fit. Maybe Harley needs to verify this for sure.
My next questions is for the guys that have shot sabotless and not knurled bullets,what is your bore size compared to bullet size.
Believe me,I'm not trying to knock knurling because I have seen repeated excellent results but is it necessary if the right fit is obtained without knurling?
One reason I ask is it seems we are alone knurling with are Savages compared to the other custom venders. I have seen excellent groups from non-knurled and knurled bullets. I'm not after a fight,I'm just thick headed.
I think Harleys gun shoots well because his bullet to bore fit is what his gun likes. The knurling only gets him to that resistance. The non-knurled bullet at the right size should be able to meet that same resistance, right! Help me if I'm missing something! Thanks Rex
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Post by Harley on Feb 27, 2009 10:49:16 GMT -5
Rex, I think you are correct in all you say. I knurl because it works for me. The "press fit" you describe seems to work because it irons out any variances among bullets and results in a uniform seal (throughout all the bullets) that I don't think is significantly affected by small changes in barrel fouling.
As I've noted before, I did lap a .449 die and used those resized bullets without knurling. I had no misfires, but my groups were much larger than the knurled-bullet groups. I think that was because I didn't do enough lapping and/or I didn't get a good concentric lap on the die. I think, though, that a non-knurled bullet would be more sensitive to differences in barrel fouling from shot to shot.
I know RB has managed to lap barrels so that no knurling is required; I don't know what groups he has obtained that way, but assume they are good.
I wish I could send my .449 die to someone for lapping, but for that to work I think I'd have to send the rifle, also, so that groups could be fired after each lap session to see the results.
Knurling a bullet adds maybe a minute to the process; I can live with that and can't fault the results.
Harley
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Post by edge on Feb 27, 2009 10:56:03 GMT -5
A couple of years ago before there was any information on size, I took some SST's and squeezed them down in a 5C lathe collet. I only squeezed most of the bearing surface down to about 0.449, and only about 1/8 inch of bearing was 0.452 ( actually it swelled a bit). The bullet was more or less mushroom shaped and the shank fell into the bore up to the swelled top portion. A quick shove with a short starter was all that was needed to get it into the bore, and they shot well. dougva.proboards.com/index.cgi?board=Savage&action=display&thread=3171&page=2edge.
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Post by Harley on Feb 27, 2009 11:05:53 GMT -5
Edge, that one group is intriguing; did you follow up? When squeezing the bullet were you just guestimating, curious what would happen; or, had you first measured the barrel and done some arithmetic? Why do you think they shot so well? Could the swelled band have maintained bullet inertia long enough for the rest of the bullet to obturate? Otherwise, I'd think the bullet would yaw along the way to exiting the barrel.
Harley
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Post by rexxer on Feb 27, 2009 11:12:01 GMT -5
Harley- Maybe your knurled bullets scrape your bore clean each time you load! : ;D
Knurling the bullet would have less bearing surface on the bore. If the bore starts to foul a small amount it might have more effect on the non-knurled bullet. This could change loading forces and might change accuracy. Just guessing!!!
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Post by rexxer on Feb 27, 2009 11:15:41 GMT -5
Edge- wow Might have to tell us more to the story!!
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Post by edge on Feb 27, 2009 11:17:21 GMT -5
I have not fired more than a dozen shots sabotless since that time since it was never really my interest. Basically all I did was to squeeze a bullet and run out side to see if I could load it. After about 10 bullets I found what seemed like a good fit....nothing very scientific, it loaded and felt good Since the top "mushroom" is oversize, it get engraved during loading so ensures that it has to spin when coming back out. That is the same reason that I like a knurled bullet that gets engraved when loading...it just can't slide down the bore and must spin which helps it obturate. edge.
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Post by rangeball on Feb 27, 2009 11:17:39 GMT -5
It seems like a sized bullet would have to be smaller than the knurled bullet, as it's resistance would be the entire bearing surface versus just the raised portions of the knurled bullet, unless I'm missing something?
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Post by rbinar on Feb 27, 2009 11:50:45 GMT -5
8-)I've had no trouble getting non-knurled bullets to shoot. However the ones that work best are soft jacketed the solids are harder to get working.
There are all sorts of things that work. Though some statements such as: "many have had success knurling" are true it does not tell the whole story. You can probably have all the accuracy you want without it.
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Post by sw on Feb 27, 2009 12:07:35 GMT -5
I think I can help with this answer. I have a barrel that RB lapped to where a 275BE is a snug fit. I have some "virgin" 275BEs, AND I have some resized 275BEs from Harley that have been knurled. I will shoot both with his "award winning" load of 12/46, compare velocities and accuracy of these two bullets. Surprisingly, they fit about the same. Maybe can shoot Sunday - windy today and snow and windy tomorrow(20G30).
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Post by rexxer on Feb 27, 2009 12:33:13 GMT -5
rangeball-I agree a non-knurled bullet would have lesser of an interference fit than knurled.
I was hoping rb might gives us some numbers for the non-knurled fit. He probably has about as much experience as anybody!
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Post by rexxer on Feb 27, 2009 12:36:13 GMT -5
sw- Sounds like a good idea! Is there any way you could get a loading force reading? Thanks
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Post by rangeball on Feb 27, 2009 12:57:50 GMT -5
rangeball-I agree a non-knurled bullet would have lesser of an interference fit than knurled. Rex, I posted my answer before reading your post that basically said the same thing I was thinking. Sorry for the duplication
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Post by rexxer on Feb 27, 2009 13:34:14 GMT -5
rangeball_ I'm slow at typing!!! I do it all the time!
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Post by Harley on Feb 27, 2009 13:42:40 GMT -5
Steve, that's a unique opportunity to test-compare, but keep in mind that I custom-knurled those bullets for my own rifle; if yours has a different bore diameter I wouldn't expect you to get the same results I do. Of course, I do so much over-knurling that you just might. Looking forward to finding out.
BTW, my load is 12/47, not 12/46, for what that's worth.
Harley
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Post by Dave W on Feb 27, 2009 14:31:27 GMT -5
My bore is a perfect fit for Parker BE's, sorry I can't tell you the exact size though. The 250 loads looser than a 275 but either is a sub MOA shooter. I ran one of each through a clean barrel, takes between 45-55 lbs of force on a bathroom scale to get them started, once they engrave a little, the resistance declines into the 30-40 lb. range to shove them home. Once some copper fouling builds up resistance will increase but not a whole lot. You are probably still going to need to knurl since the bullet does not come out uniform along the bearing surface, the base is smaller than the top of the bearing surface, Harley said he has found the same thing with his die, sort of like what Edge was talking about. Smokeeter uses a heavy custom die to size and said his bullets come out uniform without the spring back like I get, so a heavy custom die might be in order if you want to do away with knurling. I did talk to Pete about making some of these heavier dies for the members, just not sure it is needed since Harleys gun shoots so well using a Lee and not sure on a cost as of yet. Keep in mind also, different bullets size differently through my die, I would like to know if Smokeeters bullets come out uniform regardless of bullet construction. I'm not sure there is an advantage either of knurled versus unsized. I shot this group a week or so ago alternating between the 300SST and 300XTP to see if the smaller and looser XTP shot without the flier I get with the SST. I choked on the last shot with the XTP, this was a pull that I called, the SST was without a doubt not a pull. I think I need another die to get the SST to work but I need to shoot the XTP some more to see if I develop some fliers like the SST to be sure and I plan to start shooting the 250SST to see how it fares versus the Parkers at 200yds. On second thought knurling might not be needed, the 300XTP goes about halfway into the bore like Edge was doing, I'll have to try some knurled and unknurled to see if there is any difference.
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Post by Harley on Feb 27, 2009 16:20:33 GMT -5
DaveW, what's the complete load you use for the 300 XTP? They were unknurled? I'm very impressed with that group. If I'd shot such a small 3-shot group I probably wouldn't have risked it with shots four and five.
Harley
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Post by Dave W on Feb 27, 2009 16:35:50 GMT -5
DaveW, what's the complete load you use for the 300 XTP? They were unknurled? I'm very impressed with that group. If I'd shot such a small 3-shot group I probably wouldn't have risked it with shots four and five. Harley They were knurled Lloyd. 53.5gr H4198 and two .030 veggies, swabbed with alcohol between shots. There was approx. a 20fps spread in velocity for the 5 shots with 3 shooting 2306fps, the other two were like 2296 and 2314, not sure but I remember the 3 shots timing the same. I shot a 3 shot 100yd group similar to what you have posted the first time I tried this load. Thanks for the comment. It's that darn Richards fault for the 5 shot group.
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Post by Harley on Feb 27, 2009 16:39:49 GMT -5
I'm standing my ground on 3-shot groups; life is hard enough as it is.
Do you see any reason you couldn't (if you chose) substitute one dry wool wad for the veggie?
Harley
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Post by rbinar on Feb 27, 2009 16:39:53 GMT -5
rangeball-I agree a non-knurled bullet would have lesser of an interference fit than knurled. I was hoping rb might gives us some numbers for the non-knurled fit. He probably has about as much experience as anybody! I am sorry I can't. I guess I'm too old. My measurements don't seem to be close to what I've seen here. Besides I size the barrel not the bullet and I size it to feel not a measurement. I would say this to those adverse to sizing: I've never (I mean NEVER) had to size in 40 caliber but I may have to knurl on some barrels. The above image is a 10 shot group I shot with the un-sized and un-knurled 300 grain Parker with 53 grains of H4198 and a 1/8" woolen wad.
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Post by smokeeter on Feb 27, 2009 16:57:25 GMT -5
rangeball-I agree a non-knurled bullet would have lesser of an interference fit than knurled. I was hoping rb might gives us some numbers for the non-knurled fit. He probably has about as much experience as anybody! I am sorry I can't. I guess I'm too old. My measurements don't seem to be close to what I've seen here. Besides I size the barrel not the bullet and I size it to feel not a measurement. I would say this to those adverse to sizing: I've never (I mean NEVER) had to size in 40 caliber but I may have to knurl on some barrels. The above image is a 10 shot group I shot with the un-sized and un-knurled 300 grain Parker with 53 grains of H4198 and a 1/8" woolen wad. Hey Rick , I can only count 5 holes there, u sure theres 10
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Post by rbinar on Feb 27, 2009 17:02:58 GMT -5
Hey Rick , I can only count 5 holes there, u sure theres 10 I don't know how many holes there are but I'm sure I shot more than 5. Perhaps I missed the whole target 5 times.
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Post by Richard on Feb 27, 2009 22:26:08 GMT -5
Look at it this way Dave............At least you have a more realistic account of what the load is capable of. Think "real word" not just braggin' rights. I know I sound like a broken record, but why do you think at bench rest matches they require five....five shot groups that form an aggregate? This is what accuracy is about. Not one or two lucky groups. And at that, not one or two "puny" three shot groups. This is what seperates the men from the boys. ;D Richard
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Post by Harley on Feb 27, 2009 22:56:01 GMT -5
I'm still standing my ground on 3-shot groups with the 10 MLII. I'm not talking about "one or two lucky groups", Richard. I'm talking about a body of work, consecutive groups that together reveal what the rifle is capable of doing. I know this isn't up to benchrest standards, but this is not benchrest, and this is not a benchrest rifle. I'd like to cite my own recent experience as an example: After fouling my barrel at 300 yards, I shot one and only one 3-shot group of ~1.7". My very next group was at 400 yards with the same load and with the barrel untouched since the 300 yard group. It measured ~1.8". I've no doubt you could say I had two "lucky" 3-shot groups in a row, but I don't think so. Unhappily, my scope broke on the last shot and I couldn't continue. When Leupold returns it I'll see if I can repeat. If I can't, I'll be disappointed but still proud of the earlier groups.
I certainly agree that it is misleading to cull any one good group to show to the Board.
Harley
P.S.: In the "real world" in which I shoot an accurate one-shot group is enough.
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Post by Dave W on Feb 28, 2009 0:34:54 GMT -5
I'm still standing my ground on 3-shot groups with the 10 MLII. I'm not talking about "one or two lucky groups", Richard. I'm talking about a body of work, consecutive groups that together reveal what the rifle is capable of doing. I know this isn't up to benchrest standards, but this is not benchrest, and this is not a benchrest rifle. I'd like to cite my own recent experience as an example: After fouling my barrel at 300 yards, I shot one and only one 3-shot group of ~1.7". My very next group was at 400 yards with the same load and with the barrel untouched since the 300 yard group. It measured ~1.8". I've no doubt you could say I had two "lucky" 3-shot groups in a row, but I don't think so. Unhappily, my scope broke on the last shot and I couldn't continue. When Leupold returns it I'll see if I can repeat. If I can't, I'll be disappointed but still proud of the earlier groups. I certainly agree that it is misleading to cull any one good group to show to the Board. Harley P.S.: In the "real world" in which I shoot an accurate one-shot group is enough. Richard, I do not disagree with you, it is a valid point and I wish you had never planted that seed in my head, but I have always followed Harleys point of view on the subject. The groups I post are repeatable 3 shot groups or very close to it. I don't post loose groups because I don't shoot them, I just feel there is no need to show what did not work, but at the same time what works for me certainly may not work for others. Harley also makes a good point about these not being BR guns, the 6PPC shooters I watch could put 5 into one of those .45 holes sometimes, but those guns have very little kick and they just slide them back up into place on the rest and crack another one off. That is not meant to take away from their skill, I just don't know if it is a fair comparison for what we are trying to do considering recoil and other variables. This has gotten way off base, the reason for posting the group was to show that I'm not sure unsized Parkers have any advantage over knurled bullets. Harley, I think RB answered your question about the wad with a resounding YES by the looks of his group.
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Post by DBinNY on Feb 28, 2009 10:40:28 GMT -5
Boys, you are both right but you are measuring different things. Richard's game requires shooting 5 shot groups. Fine. Harley has very good and consistent 3 shot groups. Fine. I have no doubt that there are lots of board members who are hunters that would value the ability place that first 1 shot right on the money above shooting small groups. All viewpoints are valid and correct. They are just different.
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Post by edge on Feb 28, 2009 11:06:28 GMT -5
IMO, there are more factors that are not being considered for a hunting rifle!
If you are a target shooter, and your nerves do not bother you shooting 5 shot groups, then a 5 shot group may be good from a statistical standpoint. If on the other hand you are a hunter, then shoot as many shots as you feel comfortable shooting, and that might be just one! Many hunters, may get nervous shooting more that 3 shots especially when the group is not enlarging.
If this is you, than you will be very hard pressed to ever get a good 5 shot group and you may be dismissing loads unnecessarily! As long as you don't adjust your scope, and have a good aiming spot to locate your groups against then 100 1 shot groups is statistically the same as 20 5 shot groups.
Remember many target shooters get so excited at the sight of a buck that they can't hit them at close range, buck fever, and there certainly is the same type of target fever with hunters trying to shoot small groups!
edge.
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Post by dannoboone on Feb 28, 2009 12:46:01 GMT -5
Many hunters, may get nervous shooting more that 3 shots especially when the group is not enlarging. If this is you, than you will be very hard pressed to ever get a good 5 shot group and you may be dismissing loads unnecessarily! Remember many target shooters get so excited at the sight of a buck that they can't hit them at close range, buck fever, and there certainly is the same type of target fever with hunters trying to shoot small groups! edge. AMEN, here! Although buck fever has been a pretty mute subject with this hunter (just happened once, cuz I had too long to think about it, but got over it before taking my 1st 10MLII buck), those 5-shot groups are something else, entirely. Doesn't matter if it is CF or ML, if those first 4 shots are making a fantastic group, I'll blow the 5th EVERY TIME!!
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Post by sw on Feb 28, 2009 14:41:18 GMT -5
I'm going to share some thoughts that both RB and Edge have mentioned, and I agree with. Possibly neither has stated everything in the following statement but each at least parts of it. IE, I'm not taking credit for these thoughts: remember, I'm like the Japanese car manufacturer. With the bullets and bores available for us to use, knurling of slightly undersized bullets will likely provide the most accurate groups. Like it or not, the Parkers are not uniformly round: this is a problem. The loading resistance, round to round, varies considerably in my 450 PacNor barrel. However, the loading resistance in my 401 barrel of knurled 40 cal bullets is very consistent as is the loading resistance of knurled resized Parkers in my 448 barrel. If a resized bullet is slightly smaller than the land to land distance and then knurled to ever so slightly larger than the land to land didtance, the knurled surface gives comparatively easily and a nice snug fit occurs without undue pressure to get the bullet down the bore. The unknurled bullet being loaded into a barrel of just the right size will much more resistance to get the solid jacket down the lands: if it's slightly out of round(Parker 275BE) it will be all the harder. If one bullet takes 50# to get down and the next takes 120# to get down, accuracy will suffer. So, I prefer a bullet that is slightly smaller(appx 0.001") and is then knurled slightly to just get a snug fit.
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Post by smokeless77 on Feb 28, 2009 18:45:53 GMT -5
When the trigger is pulled and the bullet swells into the bore of the rifle, wouldn't that take care of any out of round bullet.
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