wsimpso1
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Posts posted by wsimpso1
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Hi, my 45 ACP has always needed more powder than book values to make velocity, and many of the loads are dirty too, even when other folks report the load to be clean.
I know that it is not a miscalibrated scale because I have other guns (rifles and a Para in .40) that match up very well on velocity vs powder charge. I also know that it is not a miscalibrated chorngraph because I have lined up mine and others and recorded shot-by shot on them, and they are usually within a few fps, with the differences between gadgets looking fairly random.
A couple of for-instances:
Using Rem primers, N310, and Montana Gold 230 FMJ, I needed 4.7 grains to get 750 fps, and it was DIRTY;
Same batch of Rem primers, WIN 230 g FMJ and 5.0g of N320 to get 750 fps, but at least it was clean;
Now I am trying to get N310 to work with 200 grain Master Blasters, and it takes 4.7 grains to go 875 fps, and it is a little dirty.
The barrel is stainless and came from Olympic Arms about 15 years ago, but never saw much shooting until 2004, when I started USPSA and IDPA. It has about 4000 rounds through it, and the N320 load with WIN is quite accurate and repeatable. Probably should stay with it...
My suspicion is that the barrel is a little large in land and groove diameters, so I may be best served to fit a new barrel. What do you folks all think?
Billski
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Hi, I recently heard about and then went to website - http://www.actshooters.com/ - for ACTS matches. They are near me and are doing tactical rifle matches. Anybody been to one of their matches? Anybody got anything else to say about them?
Billski
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The best rifle loading measure I have used yet is the Harrels, about the same money as the Quick Measure but it gets raves all over. No set up for progressives though.
My Hornady LNL progressive came with Hornady measure, and it is great for loading 223 Rem ammo for High Power. I could never detect variability on individual powder throws (well under 0.1 g) at rifle quantities and it is way cheaper than the Quick Measure. I have a metering insert for each of my High Power loads, and a micrometer for everything else. They interchange easily. It just plain works great with H4895, RL15, N135, etc.
Billski
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Rika,
I hope that the Ladies Camp went well. They always sound like fun, and I am wondering if there is one for old farts (I start competing Senior category in April).
I too have had shoulder problems, and ID'd it as tendonitis or maybe rotator cuff. The doc said that mine was not rotator cuff or tendenitis, even though it felt like tendonitis did near other joints. At physical therapy, they said that the difficulty I had would be solved by strengthening the small muscles that hold the shoulder together. They put me on heat, ultrasound, and (I forget the name) electrical stimulation of the shoulder muscles, then an exercise and stretching program. It was designed as are my exercises for my feet on working the the small but essential muscles that hold things in shape, and it worked. For folks in SE Michigan, U of M Medsport is just great.
The moral is (as you have indicated) get it diagnosed and treated, because there are several things that can feel similar in the shoulder.
Billski
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Back before I discovered USPSA and IDPA, I used to shoot High Power with moly coated jacketed bullets. Accurate (High Power standards are pretty high) time between cleanings in a High Power gun is usually around a couple hundred rounds, and moly bullets extend that, and then take copper deposition on the bore to a lower level, so cleaning is easier too. Kroil and and a wipe with JB at 400 rounds vs copper solvents and then a bunch of JB every 200 rounds. Remember, High Power means 60,000 psi and much higher temperatures than we use even in an Open pistol. At .45 ACP pressures and temperatures, we do not wear out throats and we do not have copper deposition on our bores either. Some of us might have rough grooves and scrub copper from our bullets, but rifles erode throats, vaporize jacket from the bullet base and then it condenses on the bore as the gases expand and cool. And Moly did cause many of us to bump powder charges to get the same velocity. Some folks recognized that bullet pull dropped with moly bullets, and polished down their neck expansion ball to get another 0.001" of bullet grip. We find that we need a smaller difference in powder charge between naked and moly when we do this.
Biggest problem cited by any High Power 'smith was that if you load a round without powder, moly bullets will squib far enough down the bore to allow another round to chamber and blow up the rifle. Plain jacket bullets are less likely to do this. Hmm. So I tested squibs with my modified neck expander and there was no way to get another round in the chamber. Never had a problem, they shoot great, and you can do a practice before a weekend match, and not clean through the interval with great accuracy.
So what does this mean to us? Moly and Poly means that you might need more powder to get the same velocity. Let your chrono be your guide. My Master Blasters Bullets in .40 were right on their website's recommendation of 4.7 N320 for safe USPSA Major. In 45, I am having poor results with N320 (need more powder and they are dirty!) so I think that my "slow" barrel is resulting in the powder not getting lit reliably. Rem primers... Maybe I shall try some of those thousands of Federal Rifle primers I have sitting around from my .30 cal High Power days. Yes, I am old. This just proves that all barrels are individuals..
Billski
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I had trouble with N310 and 230 g jacketed bullets in my .45.
I had a load of 4.6 g and it went about 750 ft/s, but with its variation it was comfortably Major. Soft shooting, pretty large velocity variation, and dirty, but reliable.
Then I softened the taper on my mouth belling tool, and the load became downright psychotic. Small powder charge changes produced large changes in behaviour and odd velocity distributions:
4.6 grains gave 720 ft/sec, and was really sooty. Most were lower than 720, and one out of ten would be around 780 ft/sec;
4.7 grains gave 820 ft/sec and the cases were clean! Most were higher than 820 and one or two would be down around 730 ft/sec.
It seems that the bullet pull was lowered by the reduced taper, and most of the time, the powder was not getting lit with the lighter charge. The smallest amount heavier charge would usually get lit. My barrel is a touch "loose" too, with both lands and grooves on the large end of the acceptable size range. I set that jug of powder into the back of the cabinet and try it with new loads now and then.
It seems that VihtaVouri knew what they were doing when they initially skipped this powder in certain calibers and bullets.
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I actually have three reasons not to dump rounds. The first two relate to your own personal ethics, and possibly to the tolerance or lack therof in your SO's. The last one has to do with poisoning your mental state:
It is cheating;
It requires lying - Even if you do not say it, the lie of "I made up a bad shot" is still there;
To get away with it, you would really need to deliberately miss or shoot a -3. Now, if you have been paying attention to what Brian and many of the others on this forum are trying to teach us, you would know what comes next. This means deliberately doing something that you really do not to do. Do you really want to poison the process of making center hits automatic? Shooting for something other than the highest scoring parts of the target are bad for your mental capacity to shoot as fast as you can see.
I know, what about leading movers and swingers, or dealing with no shoots? Don't we have to aim off of the 0/A box for those shots? Sure we do, and we develop our mindset for hitting them well too. And we are always focused on getting good hits too.
Practicing and metally rehearsing bad shots is a net loser for our total technique. So, even if you are a cheat and liar, and the issue of ethics does not bother you (and that will get around and result in FTDR and procedural penalties), it will result in downgrading your total game.
Billski
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Well, it is not new, but there are a whole variety of hieghts available for the front in Fire Sights from Williams. Combine that with their ghost ring reciever sight and you have a simple, sturdy sight that works well with slugs and small targets and still allows you to shoot clays instinctively...
Billski
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Followup - With the front edge of the mag lips at 0.385", sharp edges broken, front 0.10" of each feed lip polished lightly, and the slide stop surface adjusted to lock the gun open at the right place, these mags run 100%. The length of the feed lips did not need to be shortened at all.
Thanks again for the help.
Billski
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George is right on the money. Take it to a 'smith that understands AR's. I too use Loctite, and it works great. It may take heat to disassemble, but that is better than having it come apart when you do not want it to come apart.
Billski
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The AR15, like many guns, can be screwed up several ways. The barrel nut is a likely problem, as is the front sight base, a badly screwed up crown, a loose flash hider or brake, a loose barrel extension... Send it back and ask that they supply what your brother paid for. Bushy is likely to fix it.
Billski
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I really don't see what his age has to do with it.
We have always welcomed newcomers regardless of age to local NRA High Power and Small Bore shoots. I go to IDPA and USPSA matches where there are adults who are unknown to the MD and RO's/SO's, and they are allowed to shoot. Who's to say that they are competent?
The whole purpose of the RO/SO is to watch every shooter like a hawk, and call 'em as they see 'em. If any shooter's gun handling or other behaviour pops a rule boundary, you gotta call it, and if it pops a DQ boundary, out they go. And if the shooter handles his or her self well, compliment them on it. Where does the fact that the shooter is a kid have anything to do with it?
I frequently hear the question during the shooter's meeting "Any new shooters here?". It is sometimes followed by asking to spread them around so as to not slow down any particular squad and then they recieve what extra attention is needed from as they flow through the match. Most acquit themselves fine as they figure out the new game.
At the EAA annual fly-in, we had a qualified individual rule, that restricted flight line passes to members of EAA, AOPA, Avaiation Medical Certificate Holders, and their families. Why did we do this? We did not want people handling rare or one-of-a-kind antiques, warbirds, and homebuilt airplanes without permission, much less doing anything untoward or unsafe, like sitting a squalling child on a fabric covered wing. The assumption was there that qualified parents would be pretty good guides, and I have only rarely seen that assumption violated.
Now for rules, we have Unclassified in USPSA and IDPA, which could be plenty for the shooter. I would think that a classification in any of USPSA, IPDA, ICORE, GSSF, NRA or gun associations from other countries in the parent's hand would be qualification enough for a child's first shoot IF the parent is attending the stages. Once a shooter has a classification in one of our sports, regardless of age, the club should not be allowed to say no.
Going further and requiring that a club qualify all walkups "now" is a bit much, but I have shot at clubs where, lacking a classification card in the discipline at hand, a qualified member would walk through the requirements briefly.
Just my piece on growing the sport wisely.
Billski
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Thanks Benny, the dimensions for crimp and feed lips is VERY useful, and confirmed my feel for where they needed to be.
I stopped short of the 0.395" at the front of the lips recommended in another thread, and now they are about 0.380-0.385". With the lips set to those dimensions and the hard corners removed from the front edge of the feed lips these guys run very nicely by hand and so far are 100% in the gun. They do not fountain or spit rounds either.
I am still concerned that the release may be a bit late, but I will stop fussing and just shoot the thing.
Thanks again, Billski
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Hey tewlman,
Cool stuff, that SolidWorks/COSMOSWorks, isn't it? I have the full suite available to me and I like using it. It has gotten good use on stuff for my job as well as for the airplane project, designing landing gear legs to absorb enough energy while stay below yield strength, designing hinges and doors for flight loads, roof for rollover protection. Then there are weld stresses, inpact loadings, etc.
One thing - Elastic strain (prior to yielding) occurs at the speed of sound in the material, and is about 26,000 ft/sec in steel, so , even though the load is on and off quickly, the load gets on and off way too slowly to not be fully felt by the brake components. Plastic deformation takes more time to develop. If the stresses do indicate that they would be above yield strength, they may not move appreciably on one firing, but a succession of firings will move it and eventually be visible.
For calculations around the brake... I do not want to discourage you. I am sure that you can find the fractions of gases from anaerobic combustion of nitrocellulose and nitrogylcerine, calculate the thermal capacity of those gases, look up the thermal energy released by anaerobic combuustion of nitro cellulose and nitroglycerin, compute the temperature/sonic velocity relationships, and then the temperature/pressure at the muzzle, and then go through the powder gas drainage modeling and find an estimate of the time-force curve for the brake. It just makes my head hurt faster than "I Am My Own Grampa".
Now if someone can get an oscilliscope and strain gauged barrel and brake out to the range, I would sure love to see the results. Maybe someone has some Stresscote that they can apply to a known brake, shoot it and get an estimate of stress from that. Both methods could validate the calculations.
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I know that Benny is a great gunsmith and shooter, nearly unbeatable with a long gun, etc.
I also know that many of you believe in working with a great 'smith and then just shooting your gun. And maybe that is the best advice... Thank you.
What I really wanted was knowledge on how to make mags work or knowledge that would convince me that fooling with mags is just not wise. Heck, I am an engineer working on automatic transmissions, and I will help pull one, but I let the pros do the rebuilds. I know, reliability tuning is the realm of the pros, and how they make their living, that they are not interested in giving away for free what people would otherwise pay for, etc.
Now me, my first job after engineering school was Remington Arms. Besides arming me with gobs of good info and almost ruining a good hobby, it made me lust for doing my own work on guns. I have successfully built very accurate, reliable rifles for High Power (M-1's, AR15's, Bolt Guns), and modified my old .45 into a completely reliable accurate Ltd10/CDP. Now I have made a LTD/ESP gun and am trying to make it go from 98% to 100% reliabilty.
So, if anyone has advice on mag tuning, I am still listening.
Billski
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Hi, I am just finishing up the build on a the limited gun, and the gun was feeding for crap. Read the FAQ's, did a search, broke all of the hard corners, set the widths between feed lips at 0.385-0.395", polished the front edge of the lips.
While hand cycling the gun, it still wants to hang up some rounds on the feed ramp - the rounds are aimed such that they still hit the feed ramp, but only barely. It is so much better than before. It will not hang if I just drop the slide, but if I follow it down it can hang. I can probably open the lips a wee tad more (to 0.395") and get the nose of the round pointed higher if I have to.
Then when the round does enter the chamber, I can still get it hung up with the case on the break between feed ramp and chamber and the rim still under the last 0.040-0.060" of the feed lips. My McCormick mags in my Colt in .45ACP release the round with nearly 1/8" of clearance and it is 100%. Hmmm.
So I am wondering, should I take a bit off of the front edge of the feed lips in order to release the round at the right time and beat this failure? Shortening the lips would also improve the leverage for making the bullet ride up the feed ramp, so I can only see advantages here. Is there soemthing that I can not see that will bite and cause me to scrap any mags modified in this way?
Billski
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I campaigned the M-1 in High Power for four years (in the 1980's). Fun rifle.
There is plenty of time in High Power, so we just tried to load and get back on target with good clean positions. We got to the point where we were doing a four second reload from Sitting or Prone when we had no real time pressure.
The M1A guys have to do that rocking dismount of one magazine before going to the belt or bandolier for the next. I would bet that you could slap clips and be on the next target in 2.5-3 seconds with regularity. The next thing is that could help your time is when moving between arrays, eject the partial clip and slap a full one in.
Competitive? Naw. Big style points? Sure. We are doing this for fun, are we not?
Billski
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Zak has a pretty good estimate of gas pressure at the muzzle. Trouble is that gas pressure at the muzzle is not what you have hitting the baffles on the compensator. And if it was, well, you would have 8000 pounds on the brake. OOF! What is hitting the baffles is gases that are moving and having their direction changed. You need to know what the forces look like. Momentum resolves into Force x time, and your hard part is figuring out what the time signature is.
As the muzzle is uncorked by the bullet, the gases leaving the bore will accelerate to their local speed of sound, which is way up there (over 4000 ft/s) compared to the nominal speed of sound in ambient air (1100 ft/s), pushing the air around the muzzle away as it does so. These now very fast gases are deflected away sideways by the baffle. So the energy still contained in a barrel full of powder gases at 11000 psi and say 1800 F (1250K) is converted into kinetic energy quite efficiently. The kinetic energy for any little parcel of gas is KE=1/2*sum of (mv^2).
One way to model this is to divide up the gas in the barrel into many small parcels, all at 77 MPA, and at their own velocities to have the front most one at muzzle velocity. Then you compute the mass of each one and then make a tiny time step and update the velocities and locations, then keep going. Include the ninety degree bend at the brake and the effect of expansion cooling on the temperature and temperature effect upon the local speed of sound, keep the local velocities at or below the local speed of sound, and you should have a pretty good estimate of the time-force profile on the brake baffle…
Another way is to make use of Conservation of Momentum. The momentum from this I=mv is largely converted from axial (downrange) to lateral (sideways) by the brake, with a commensurate pull forward that varies with time. Now we can estimate how much momentum is available in the expanding powder gases. What was the powder charge? Add 0.4 grains for the primer charge. Divide by 7000 to get pounds. Multiply by .454 to get it in kg. Average gas velocity leaving the barrel can be approximated at 4000 ft/sec, divide by 3.28 to get it in m/s. Multiply the kg by the m/s and you have momentum in N-s.
Now comes the hard part. How long does this event take and what does the flow look like? Hmmm. Now, if I had a rifle with a brake on it, and an oscilloscope and some strain gages, I could find out. I would place one strain gage circumferentially on the barrel near the muzzle, and another axially on the bottom of the brake. Run the wires so that powder gases would not blow them away. The one on the barrel would show some readings as vibrations from hammer fall, primer ignition and bullet engraving into the rifling occur, and then the big change would occur as the bullet passes this strain gage, and the barrel expands under the pressure of the powder gases. This would serve to trigger the scope to record data, both the one on the brake as well as the one on the barrel. Then we can watch the strains on the barrel and the brake as the barrel is uncorked and the brake works. And generate a curve for how the gases drain out, and how this brake applies load to the barrel.
As much fun as that stuff would be to run, I have not worked in a gun lab for 20 years, so does anybody else know what the pressure-time profile looks like during the gas drain?
Another way to do these calcs without knowing what the real curves are is to estimate the upper bounds and know that the real number is somewhat below the upper bound. One upper bound would be to assume that the gases expand adiabatically (no energy lost to the surroundings), in which case the pressure at the baffle decreases with the ratio of the areas (Pbrake = Pmuzzle*Abore/Abaffle). Reality will probably be lower than this…
Another estimate exists. We have gas at 11000 psi draining out of the barrel into a 15 psi area, and cooling as it does so from somewhere around 1250 K to say 400 K, so that is lessee, about 2200 times the volume it occupied in the barrel. If it all drains out at 4000 ft/s, you can calculate an approximate time for it to all blow out. Now it will actually take longer (as the barrel drains, things will slow down), and the peak velocity may actually be higher, but this might be a reasonable number.
Typical engineering consultation costs are way too high for you to have me or anybody else do this for you. I personally would just whittle some out and go shoot them. If the baffles bend over or parts fly off of it, the thing was too flimsy. Likewise, if you bend it in use. I suspect that handling is more stressful than shooting it, so build it to survive bumping around in the trunk and bumping barricades. Do that and the odds are pretty good it will survive shooting the thing.
Good luck.
Billski
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The M-1 can be built to run in about any cartridge. Garand originally developed the rifle around a .276 cartridge and a ten round en-bloc, and I have M-1's in 30-06 and 308. The 308 will run fine with 147 through 168 grain bullets, and the 30-06 rifles will run fine with 147 through 180 grain bullets.
The difficulty is two fold:
Mil surp 7.92mm Mauser ammo out there was usually intended for bolt guns and they do not care about how the pressure curve is distributed. And so, some of it was loaded with slower powder that gives higher pressures when the bullet is near the muzzle, while others are loaded with faster powder that gives lower pressures at the muzzle. The M-1 does care how much pressure is available between the time that the bullet clears the gas port and the bullet leaves the barrel. You could easily have a gun that works with some ammo, short strokes with others, and will bend your operating rod on still other ammo;
The M-1 has more corrosion problems than bolt guns. Primer residue gets on not only the bore and chamber, but the gas cylinder and plug, the operating rod and piston, and somewhat on the breach area of the reciever. Now John Garand and Ordnance made the gas cylinder and plug and the piston part of the operating rod from stainless steel because they found out by painful history that the rifle needed it. But when you reassemble the rifle after cleaning it, you had better believe that your zero will have changed too.
For my money, I would just handload bullets and powders of the right types for the M-1, and shoot the cheap stuff in the bolt guns.
Billski
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Cool Thread. Brian, thanks for resurrecting it.
I have just built a psuedo-Para from parts and was having the exact same problem. Bullet stops on the feed ramp, nudge it and it feeds. The ramp polish is what I did last night, and I was going to leave monkeying with the mag feed lips until later. This thread confirms that I am still on the right track.
Thanks again.
Billski
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I do not like the idea of bending mags that work until you know that mags are too wide. Check the width of your mags and your mag well and then go find the government specs (DIY forum on AR15.com is where I think that I found the drawings). Make decisions after you do that. I currently have a rifle that is undersize at the back, and while it works fine with my 20's, I have some in-spec 30's that do not drop free.
Billski
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The only ones that I have ever used were constructed of a base, PVC pipes set on pegs in the base, and the cross bars had pegs that set in the pipes. There was one of these bridges every 12" or so. Bump it and it came down. People can hit them and cost them a Procedural, but why ANYONE should fall in one of these is beyond me.
You could ban reloading within the tunnel to keep the fumble factor reasonable. I would be most concerned about that if you have lateral movement in the tunnel. If the Cooper Tunnel points straight downrange, I would be less concerned because breaking the 180 is less likely.
They are fun.
Billski
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Been around semi-suto long guns too long not to speak up on these recurring comments.
First, any rifle that has its groups open up as it gets warm has a barrel problem. If you have the issue and care about it, fix it by installing a good barrel that has been properly stress relieved and either free-floated or contacting the stock in a controlled manner. Factory Mini-14 barrels tend not to be stress relieved, so they "walk" as they warm. The Mini-14 is likely to have this problem, but a Winchester built M-1 Carbine is likely to have had its rifling cut (broached) and will do less of that sort of thing.
Second, autoloading rifles (Mini-14, M-1 Carbine, AR15, etc) with reliability problems are likely to have one of four issues, and perhaps more than one: No Lube/Dirty; Bad Magazine; Chamber Problems; Too Hot Ammo.
I have seen autoloading rifles that have NEVER been cleaned or lubed, usually after they start malf'ing. The M-1 carbine and Mini-14 need the gas system cleaned a few times in a lifetime. Other than that, they need the chambers cleaned and a dot of lube on the bolt lugs and op rod contact points. Do those things and any M-1 Rifle type action will usually work great.
Magazines must be tested. For the Mini, I would obtain one of each of the types available. For any semi-auto, number them, and maybe stick a paster on it when you have a malf. Then add tick marks for subsequent malfs. Find good ones and keep them clean.
Chamber problems run from dirty, rough, out-of-shape, to throats that are too short. Match chambers for semi-sutos should be no tighter than SAAMI Min Dimension. NRA High Power demands excellent accuracy and many of us use the Wylde chamber and throat, which is basically the SAAMI chamber with an intermediate length throat. It is noted for working well even with Ball ammo. Semi-auto chambers should be lightly polished through the body and kept clean. Getting rid of the sharp points on the chamber greatly eases cleaning and extraction. They get that way from use, so why not start that way?
Some batches of military ammo will give high pressure signs even with clean military type barrels and chambers. In the slightly smaller commercial and target grade throats, they will give difficulty extracting and pop primers. And then there are the hand loaders that try to make 223 Rem into something it is not. The extra 50-100 ft/s they are getting shortens barrel life, compromises accuracy, throws primers into the trigger or action, and can cause sticky extraction as evidenced by short stroking and ripped rims.
Once someone modifies operating system, all bets are off. I have heard far too many people leap right to "drilling out the gas port" when the gun short strokes or otherwise has troubles. Don't do it unless EVERYTHING else has been eliminated. The standard gas port location/size combinations work when the rest of the gun is OK. If the gun has parts that rub, are misaligned, or greatly modified, well, the potential for mischief is great, so your 'smith had better know what he or she is doing.
My choice? If I were to buy a rifle for three-gun and starting from scratch, I would see what the distances are for matches. If everything is under 100 m (that is the case in SE Michigan), the M-1 Carbine is an excellent choice. If you have shots out to 300 m, pick the Mini-14 and maybe have it massaged or just buy an AR15 with a float tube fore-end. Indoors only? Carbine works. One other advantage of M-1 Carbine - Small rifle primers, spherical or short stick powders and cheap bullets run through the Dillon or Hornady progressive just like a pistol. Those bottleneck rifle cases require a lot more fuss to reload.
Whatever you do, have fun.
Billski
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Thanks for the referral to the previous thread. My search technique must need improvement because I did search on SPS and Magazines, and came up empty... It looks like I shall buy some Para tubes and Dawson parts, and maybe buy SPS for practice of for when they get legal. Thanks again.
Billski
My .45 Needs More Powder To Make Velocity - Why?
in 44/45 Caliber
Posted
Thanks to all for the responses.
I am not trying to save money by buying a new barrel and then reducing powder charges. Cone on now... And I already have the N310, and would like to use it up on something. I am a recoil wimp, and would love to reduce recoil a bit, which is where MB bullets and N310 come in. If the barrel does not like the ammo, it is no good. The current barrel likes WIN 230 FMJ's, but not the lead bullets (leading and inaccurate)
Now, if installing a new, ramped, cut rifling barrel that likes lead bullets lets me get to PF with less recoil and the lead bullets will pay for the new barrel in 6000 rounds, that is a Win-Win-Win deal and I should go for it over this winter. I am still thinking about that...
Billski