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Larry Gibson

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  1. I've a Shilen .35 barrel I put on a M91 Argie in .35 Remington. The barrel was ordered from Brownell's. It is an excellent barrel and shoots MOA with J bullets and very close to that with cast bullets. The rifle has a Lyman SME receiver sight on it and a post front sight. I left the barrel at 26" because i like longer barrels and can still focus on the front sight when they are that far away. My rifle favors the RCBS 35-200-FN over a full case of 4895. Velocity is 2150 fps with excellent accuracy. I killed a very nice 8 point white tail down Texas way last November with it. My intenson origionally was to shorten a .35 Whelen die about .32" and then run the Whelen cases (or '06 cases) into the die and trim them back so the case neck is just short of the reamer neck. A standard .35 Whelen finish reamer is used to finish ream the chamber and headspace to the formed cases. The AOL then is perfect for the 3" magazine of the SR actions. The cartridge then is very similar to a 9x57 and will feed and extract without problems in Mauser actions. However, the 35 Remington is working so well in that M91 that i just have not got around to finishing the project. I suggest you try 5 rounds of .35 Remington through your M95 action and see if it feeds and extracts. They do just fine in my M95 which is still 7x57. Larry Gibson
  2. Brad Yes the scope is 90 degrees to the port side. This just opens up the ejection port for easier/faster loading with big cartridges. I've found it takes a quality scope to reliably hold zero if you do this and right now this is the only rifle I've a scope mounted on as such. With the Leupold I just have to remember that left is down, right is up, up is left and down is right....or is it the other way around......... Larry Gibson
  3. Brad I have a Siamese Mauser I converted to 45-70. I have it throated long so the Barnes Original 400 gr SP can be seated to magazine length. This basically gives the case the 45-90s case capacity. I load the barnes over RL7 and run it at 2310 fps. My Oheler M43 PBL gives that load a psi of 62,000. I need to revisit the 350 gr bullets as i used to push the hornady to 2525 fps with BR748 and I've no idea what it will do with newer 748 or other powders. My barrel is 24' so if yours is at least that long you shouldn't have problems reaching 2500+ fps with the 350 gr bullets. I think the 350 SPs at those velocities are more practical than the 400 gr bullets for any game on this continant. I have a canelure tool and with that and a Lee factory crimp die I can seat to about any practical length I need to to take advantage of the mag length and case capacity. Be interesting to see what loads you come up with. Larry Gibson
  4. Are you wanting a milsurp barrel of original configuration. Or are you rebarreling one with a bad barrel that has been "sporterized"? I hav rebarreled several with commercial barrels in several calibers. I have one currently that is still a "work in progress" rebarreled to .35 Remington. It was done enough to cleanly kill this 8 point white tail last month with an RCBS 35-200-FN cast soft and slightly HP'd with a Forster HP tool. Velocity was 2150 fps. Works for me. Larry Gibson
  5. The difference between 7.62 NATO and .308W is one of pressure. The 7.62 NATO almost always has lower pressure than .308W. Now I am talking about both types of ammo being loaded to specification here. We must understand that there is some foreign 7.62 NATO ammo that does not meet NATO specifications. Either it is loaded to higher pressure or most likely to lower pressure for use in FALs and G1s. If it is loaded to NATO specs then the velocity for 145-155 gr bullets is 2800+/- fps out of a test barrel. This correlates to 2750 fps out of most 22" barrels of service rifles like the M14. Almost all quality 7.62 NATO M80 type ball ammunition (foreign and US) falls within this specification. Pressures run 50-54,000 psi(M43) which is well within the MAP of 45-65,000 psi (depending on temperature per TM 9-1305-200) for M80 ammuntion. (also remember the 7.62 NATO pressures are measured with a case mouth transducer which gives somewhat less psi readings than case mounted transducers) Some M80 type 7.62 NATO made in those countries where the FAL or G1 was the service rifle run 45-48,000 psi(M43) with subsequant lower velocities. However, M118, Special Ball and LR ammuntion has pressures in the 55-58,000 psi(M43) range. If we look at the .308W factory ammunition with 150 gr bullets we see that the advertised velocities are in the 2800-2900+ fps range. To achieve this requires more pressure. SAAMI MAP is 62,000 psi. Factory 150/180 gr ammuntion (W, F, R) generally runs 55-58,000 psi(m43). I've not found any factory ammuntion that approaches the SAAMI MAP of 62,000 psi. Thus we see the difference between .7.62 NATO and factory .308W is simply one of pressure. Both fall well within the required MAPs and all .308W ammuntion I've tested so far has fallen within the MAP for 7.62 NATO. Thus shooting either one in a rifle chambered for the other should be quite safe and well within the pressure limits of the action. Caveat; it was proffered years ago not to shoot WW .308W ammunition in M1A rifles. Many misunderstood this to mean the "higher pressure" of the WW ammuntion made it dangerous and this led to the urban myth that shooting any commercial .308W ammuntion in the M1A was dangerous because the .308W had "higher pressure". It did not. What made it dangerous was/is the thinner web of the WW case cold seperate damaging the rifle. It was/is the case that is the problem, not the pressure. Not the pressures of M118. Special Ball and now LR ammunition is right there with .308W pressures. With the thicker LC cases it is quite safe to shoot such ammuntion in M14/M1As. That's why the 7.62 case was designed with the thicker web. Unfortuneately the urban legend continues. M99s are notorious for their lack of primary extraction. Cases also must be sized more to account for the tilting of the breach block (bolt). This usually means cases must have the shoulder set back .001-.002 more for ease of chambering. Just something reloaders have to deal with if using the very fine M99 Savage. Larry Gibson
  6. Not a "dummy" question at all. Maximum Average Pressure. Many confuse MAP with Maximum Allowable pressure which it is not. Most ammuntion ends up with a MPLM (Maximum Probable Lot Mean) which is generally 2.5% above the MAP. This basically means that some lots can excede the MAP, i.e. a MAP of 62,000 psi for the .308W could have some lots acceptable with a MAP of 63,550 psi. I should say here I've not found any .308W ot 7.62 NATO that approches anywhere neare that. Just because the MAP is 62,000 doesn't mean all ammuntion is loaded to that. SAAMI proof loads run 30-40% over the MPLM. The MPLM is the pressure firearms should be designed to operate at. Have I confused everyone. Larry Gibson
  7. Decent article and basicly correct. I've pressure tested quite a bit of commercial .308W and 7.62 NATO and know what the difference is. Only correction I would add to the article is that US NATO ammunition is now tested with a casemouth transducer instead of the CUP method he describes. Larry Gibson
  8. Measuring .22H pressures in a 21" Contender barrel using the Oehler M43 show Winchester factory 46 HPs have a MAP of 24,900 psi(M43) at 2514 fps. The classic load of 11.5 gr H4227 under a Hornady 45 gr bullet gives 26,000 psi(M43) at 2539 fps. The 45 gr Hornady bullet over 12.5 gr H110 gives 29,400 psi(M43) at 2840 fps. I'll find out what 13 gr LilGun gives with 40 and 45 gr bullets when the weather improves but the velocities are 3020 fps and 2940 fps with excellent accuracy respectively out of my 24" barreled Savage M40. Larry Gibson
  9. Dr. Hess Here is a report on the first test of the GCs I make vs Hornady's. I’d cast up 6-700 bullets with the GB C325-190-FN 6 cavity mould several weeks back. They’d finally aged as I let them air cool. Alloy was 60/40 WW/linotype. A friend had given me 350 +/- 1939 Turk 8x57 cases he’d pulled the bullets and powder out of. He didn’t like using corrosive primers so he gave me the cases. I neck sized them with my Redding NS die and belled the case mouth with a standard M-die. My intention was to load them as “throw away” cases for perhaps a jack rabbit shoot or two this winter. I usually pick up my cases and would in this case and dispose of them properly but if I lost one or two in the sage brush I wouldn’t have nightmares about it like with my W-W cases. The load would be a proven one with that bullet, comfortable to shoot, accurate and powerful enough for 200 yard shots. Some times jacks like to run out a ways and sit. I would load them with 31 gr of milsurp 4895 and put a ¾ gr Dacron filler over the powder. The bullets would be sized .325 and lubed with Javelina. One of the members here made me a couple GC makers and they work very well. One will make .30 and .31 GCs and the other makes .32 GCs for the my 8 mm cast bullets. I made close to 1000 GC one evening while watching a couple good movies. I set a lead block on one leg and work off that. I purchase 50’ x 6” rolls of .012” brass stock and cut it into ½” wide strips. These “feed” in the GC maker real well. I can get close to 2800 8mm GCs per roll of brass stock. The cost is about $9-10 per 1000. The GCs using the .012” shim stock crimp onto the shanks of all my 8mm cast bullets. Beer can and other tin can material are not thick enough and have to be doubled to work. I could go the beer can route or other types of cans but the brass shim stock is easy to work with and makes good GCs. A photo is below of the GC maker, some cast C325-190-FNs, some loaded cartridges and some of the home made GCs. The thought struck me as I was seating them on the cast bullets; how good are my home made GCs? So I put some Hornady GC on some of the bullets and kept them separate throughout the loading process. I got to the range today to test the GC difference. I was using my M24.47 M98 Mauser for the test. This rifle is in full military trim with the exception that she wears a Leupold 6X scope. This rifle will shoot Sierra 175 SPs into moa or better. It also has been a very good cast bullet shooter. Got it close to zero in less than 10 rounds and cleaned the barrel and let it cool off. Speaking of “cool”; it was pretty chilly at the range today. Cold and damp and a 3-5 MPH wind coming off the Puget Sound from 9-10 o’clock. With the barrel clean I fired 2 foulers and then fired 10 shots for group using the Hornady GC’d bullets. The 10 shot group size was 1.55”. Velocity was right at 1800 fps. I let the barrel cool and then cleaned it. I then shot 2 foulers and another 10 shot group with my home made GCs. Velocity was again right at 1800 fps and the group size was 1.65”. Interesting note was that after the 2 foulers were fired with each group the first 5 shots went into right at 1”. That demonstrates that the bullets from this particular GB mould are pretty uniform I did not weigh the bullets or attempt to sort by cavity. I just cast them and gave a visual inspection of the bullet for defects when seating the GC. Not a conclusive test but the results were close enough given the 10 shot groups that it the home made GCs I made are very comparable to Hornady's for accuracy. Further testing with more of the 8mms and then some .30 & .31s will be done down the road. Sure can’t complain so far….now where are those pesky wabbits……. Larry Gibson
  10. The Lyman "New Edition" #43 manual has loads high lighted as "potentially most accurate" for each cartridge mentioned. Larry Gibson
  11. Wow, that is a tough one for sure. However one must make choice for the country based on practicality not personal choice. If one chose the 6.5 or the 8mm how could you make use of any captured ammuntion and weapons without much logistical and training problems? The old Dictator might not take too kindly to that! Serious considerations would have to given who you are allied with and who are your enemies. Also in what direction does the old Dictator want to strike out?. Another consideration is supply since you don't make your own ammo. How easy would it be to get ammo from an ally or from Europe and what is the cost? Boils down to a choice between 7x57 or the 7.65 Argentine. Dending on where the "Republic De Banana" was located SA would also be a consideration. If I was educated and had kept up on current developments of ammuntion I probably would opt for the 7.65 because of machinegun useage. My personal choice is also the 7.65. However that is based on the buitiful rifles made for it and it's suitability with cast bullets. Those would not be a consideration in the above. Larry Gibson
  12. AzRedneck All of my "sources" (probably the same as yours) also list the 7.65 as Equador's cartridge. When I first got this ammo I tried to look it up but found nothing. I'd post a picture but I don't know how to change the format from JPE to one compatable with this forum. I've got some '54 and '55 of this ammo. It comes on steel 5 shot strippers in 15 round boxes. The boxes have "15 Cartouchos "SS", Cal. 7,92 mm." and the Equadoran crest with "Ejercito" over the top and "Equatoriano" underneath. The cartridges are headstamped with "7,92" on top, an "A" on both sides of the primer and the year "1954" or "1955" underneath the primer. They are very nice brass cases with berdan primers, 45 gr of the typical German type flake powder and a cupro-nickel 196 gr "SS" bullet. A recent 10 shot test of each lot produced 2457 fps with 52,800 psi(M43) MAP for the '54 and 2479 fps with 53,500 psi(M43) MAP for the '55. I had one or two misfires in each string with the round firing on the second strike. The data of these were within the normal shot to shot variation of the tested lot and showed no abnormalty when they did fire. They misfire in all of my M98s like this so it's not the rifle. Accuracy is between 3-4 moa for both lots with 10 shot strings. I agree with you that Equador probably scored on some German surplus after the war and used the 8x57, perhaps as substandard issue. Larry Gibson
  13. AzRedneck At least one South American country used the 8x57; Equador. I've been shooting about 1500 rounds of their ammo. Larry Gibson
  14. I wouldn't exactly say the 7.65 was "in it's ORIGINAL form and loading, it was somewhat inferior to the 8 x 57". The 8x57 came about 10 years after the 7.65 and had the benifity of a lot of powder and bullet development in those 10 years. Yes the 8x57 with it's spitzer sahped bullet was superior to the 210 gr RN of the first 7.65 loading. However the 7.65 was quickly loaded with a 185 gr FMJBT that was the ballistic twin of the 196 gr 8mm FMJBT. With both at 2450 fps or so there's not much difference between them. Norma and Hornady 150 gr loadings are the ballistic equal of the 7.62x51 NATO (with slightly lower pressures due to the larger case capacity of the 7.65) given equal barrel lengths. In the M98 actioned M1909 both the 7.65 and the 8mm, when loaded with equal weight bullets at the same pressure are pretty equal ballistically. I shoot both cartridges extensively and wouldn't give a nickel for any difference between the two. However when comparing the military cartridges of each it is a toss up. The 196 gr load of the 8x57 is pretty much equal to the 186 gr 7.65 load. On the other hand with the lighter weight bullets the German and Turk milsurp ammo is considerably hotter than the few comparable 7.65 milsurp rounds I've tested. Interesting topic. Larry Gibson
  15. "GB GC" means that over on the Cast Boolet forums they do Group Buys (the GB) on custom moulds and also have a guy who makes GCs for a bit less than Hornady's or Lyman's. The GC is for Gas Check. Sorry, everyone over there is used to those abreviations so I just used them here without thinking. Larry Gibson
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