A No. 5 rifle should have standard - within tolerance limits- bore dimensions, and the same twist as a No.4. The 220gr. is not unlike the 215gr. of the Mk.VI cartridge. Watch the throat contact - rifles set up for Mk. VI ammunition have a long throat compared to ones intended for Mk. VII. .303 and .30-40 are peas in a pod ballistically, so the load should be fine. Probably just a situation with the one rifle. Have you tried Steve's 200gr bullets from 3w.303British.com? I plan on getting some for use in Mk.II Rosses.
303 to 308?
- Thread starter maxim08
- Start date
The #4 action should be able to take the pressure; see P.O. Ackley's action tests from quite a few years ago. There are a lot of DCRA rifles ythat started as .303s and finished with 7.62X51 barrels. The .303 Epps will give greatly improved performance over the basic .303.
These are all conversions that can be done by a competant, experienced gunsmith. (notice the PERIOD)
"Off-the-rack" economy cars can also be converted into hot little "street racers". It happens all of the time; people get killed, not always the racers.
If you want to modify a Lee-Enfield into something else, there are lots of gunsmiths around that will let you help do the work, if you are willing to pay a large multiple of their usual rate.
Blowing up rifles is exciting, but not really a great deal of fun, if you have any brains to begin with!
These are all conversions that can be done by a competant, experienced gunsmith. (notice the PERIOD)
"Off-the-rack" economy cars can also be converted into hot little "street racers". It happens all of the time; people get killed, not always the racers.
If you want to modify a Lee-Enfield into something else, there are lots of gunsmiths around that will let you help do the work, if you are willing to pay a large multiple of their usual rate.
Blowing up rifles is exciting, but not really a great deal of fun, if you have any brains to begin with!
Very good point savagefan 
Few years ago, I meet a fella who told me that he had done a "scientific" test to find out the strenght of a # 4 Lee-Enfield action by handloading a hot load in front of a .338 bullet, then chambered this dangerous load into the .303 rifle and attached a long line to the trigger, and fired the gun/bomb.
The barrel did blow up, however the action withstood the extreme pressure and functioned flawlessly afterwards.
How "scientific" can a gunsmith be, in determining if a # 4 Lee-Enfield actions is sound and strong enough to be converted to handle the more powerful 7.62 Nato caliber, considering that no gunsmith have x-ray equipment or other sophisticated means of determining, other than their eyeballs, to pronounce if a particular # 4 Lee-Enfield is strong for a convertion to a 7.62 Nato caliber, and therefore supposed to have better judgment than your eyeballs, if your # 4 lee-Enfield action is strong enough for a 7.62 Nato convertions ?
Have any gunsmith, eyeball-judging the safety and strength of a otherwise undamaged # 4 Lee-Enfield action, ever refused a convertions to the 7.62 Nato caliber, and thus forfieted his $ 500 + income in doing so ?
Which comes down to, that my eyeball judgement and experience. is as good as any gunsmith's in determining if my # 4 Lee-Enfield action is strong enough to handle the pressure of the 7.62 Nato caliber, as well as being $ 500 +, cheaper ?
There has never, to the best of my knowledge, ever been any serious problems with any # 4 Lee-Enfield, gunsmith converted, to fire the more powerful 7.62 Nato, which also means that any visible undamaged, # 4 Lee-Enfield action, is plenty strong enough to handle the more powerful 7.62 Nato caliber, otherwise we would long ago have been warned against such convertions from the british, canadian and other military and civilian users of this popular convertions of the 303 British, # 4 Lee-Enfield rifle to fire the 7.62 Nato ?
Few years ago, I meet a fella who told me that he had done a "scientific" test to find out the strenght of a # 4 Lee-Enfield action by handloading a hot load in front of a .338 bullet, then chambered this dangerous load into the .303 rifle and attached a long line to the trigger, and fired the gun/bomb.
The barrel did blow up, however the action withstood the extreme pressure and functioned flawlessly afterwards.
How "scientific" can a gunsmith be, in determining if a # 4 Lee-Enfield actions is sound and strong enough to be converted to handle the more powerful 7.62 Nato caliber, considering that no gunsmith have x-ray equipment or other sophisticated means of determining, other than their eyeballs, to pronounce if a particular # 4 Lee-Enfield is strong for a convertion to a 7.62 Nato caliber, and therefore supposed to have better judgment than your eyeballs, if your # 4 lee-Enfield action is strong enough for a 7.62 Nato convertions ?
Have any gunsmith, eyeball-judging the safety and strength of a otherwise undamaged # 4 Lee-Enfield action, ever refused a convertions to the 7.62 Nato caliber, and thus forfieted his $ 500 + income in doing so ?
Which comes down to, that my eyeball judgement and experience. is as good as any gunsmith's in determining if my # 4 Lee-Enfield action is strong enough to handle the pressure of the 7.62 Nato caliber, as well as being $ 500 +, cheaper ?
There has never, to the best of my knowledge, ever been any serious problems with any # 4 Lee-Enfield, gunsmith converted, to fire the more powerful 7.62 Nato, which also means that any visible undamaged, # 4 Lee-Enfield action, is plenty strong enough to handle the more powerful 7.62 Nato caliber, otherwise we would long ago have been warned against such convertions from the british, canadian and other military and civilian users of this popular convertions of the 303 British, # 4 Lee-Enfield rifle to fire the 7.62 Nato ?
Well - There was a documented failure of a 308 converted #4 LE on this board not too long ago.
Lets get technical. The problem with these "load-em" up tests done over the years, is that they were done on a few rifles, not a population. Within a population of 303 LE's, a certain percentage will display flaws of varying sizes. A flaw of sufficient size will cause a crack to propagate in a catastrophic way, even though the surrounding metal is reasonably stressed.
At 303 pressures and stresses, the percentage of rifles having flaws of sufficient size is very low, and the rifles enjoy reliablity. At 308 pressures, the threshold flaw size is reduced, meaning a greater percentage of rifles would kaboom upon firing a very few number of shots. This concern was sufficient enough to cause the military (and Longbranch DCRA conversions) to employ x-rays and other non destructive examinations to weed out suspect actions. ( I wonder what the failure rate was?) Today, NDE is employed in the manufacture of all centrefire rifles, and other critical service components.
So if you decide to convert your old 303 to 308 you are playing the probability game, and taking a chance that very knowledgeable people were unwilling to take without safeguards. Loading up your old 303 to 308 pressures would likely expose you to more risk, given the uncertainty about the 303 barrel metallurgy.
This is one subject where ones actions shouldnt be ruled by dogma.
Lets get technical. The problem with these "load-em" up tests done over the years, is that they were done on a few rifles, not a population. Within a population of 303 LE's, a certain percentage will display flaws of varying sizes. A flaw of sufficient size will cause a crack to propagate in a catastrophic way, even though the surrounding metal is reasonably stressed.
At 303 pressures and stresses, the percentage of rifles having flaws of sufficient size is very low, and the rifles enjoy reliablity. At 308 pressures, the threshold flaw size is reduced, meaning a greater percentage of rifles would kaboom upon firing a very few number of shots. This concern was sufficient enough to cause the military (and Longbranch DCRA conversions) to employ x-rays and other non destructive examinations to weed out suspect actions. ( I wonder what the failure rate was?) Today, NDE is employed in the manufacture of all centrefire rifles, and other critical service components.
So if you decide to convert your old 303 to 308 you are playing the probability game, and taking a chance that very knowledgeable people were unwilling to take without safeguards. Loading up your old 303 to 308 pressures would likely expose you to more risk, given the uncertainty about the 303 barrel metallurgy.
This is one subject where ones actions shouldnt be ruled by dogma.
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If you know an aircraft mechanic, he should be able to do testing with penetrative dyes and black light. The testing kit is portable, small toolbox size.
The New Zealand NRA has banned all No. 4 7.62 conversions from their shoots. Everywhere else the rifles are little used in competition because they are not competitive.
Operating pressure of the .308 is about 25% higher than that of the .303. If a .308 cartridge is loaded hot, the pressure could be approaching .303 proof level. If there is any residual sizing lube on the case or if the cartridge is wet from rain, etc. backthrust will rise dramatically. When 7.62 conversions were used in competition, shooters were very careful to keep their cartridges dry. At the very least, wild shots would result from the change in back thrust and vibration pattern.
I have No. 4s converted to 7.62, both done by myself and others. I am prepared to shoot them. I would not do a conversion for someone else. There are too many variables over which I have no control.
Apart from the actual strength of the action and barrel, there is the question of how the action could handle a catastrophic case failure. Rifles may come unglued not from fracture of the steel, but from failure of the case. Anyone handloading .303 ammunition for a LE knows that the cases much be watched carefully for incipient separations, and that a broken case tool can be very handy. Does anyone know what the situation is with .308? The higher pressures must be flexing the action/compressing the bolt more. When a .303 case separates, there is little, if any gas release. What happens with a .308? The 7.62 conversions were intended for use with NATO ball exclusively, no .308 ammunition, either handloaded or factory. If .308 cases or ammunition is used, it is a whole new ball game. The .308 No. 4 mishap reported here that resulted in a person behind the line getting a metal fragment embedded in his shoulder is an example of what can happen if a case fails catastrophically. The action held, but the extractor and case fragments became missles.
How was a .338 bullet loaded into a .303 case and fired in a No. 4 rifle?
Ackley reports throating a M1917 rifle with a .35 reamer, and firing it with .35/.30-06 (basically .35 Whelan) loads, without any sign of stress or damage. The lead core bullet sized down nicely, and passed through the .30 barrel.
The New Zealand NRA has banned all No. 4 7.62 conversions from their shoots. Everywhere else the rifles are little used in competition because they are not competitive.
Operating pressure of the .308 is about 25% higher than that of the .303. If a .308 cartridge is loaded hot, the pressure could be approaching .303 proof level. If there is any residual sizing lube on the case or if the cartridge is wet from rain, etc. backthrust will rise dramatically. When 7.62 conversions were used in competition, shooters were very careful to keep their cartridges dry. At the very least, wild shots would result from the change in back thrust and vibration pattern.
I have No. 4s converted to 7.62, both done by myself and others. I am prepared to shoot them. I would not do a conversion for someone else. There are too many variables over which I have no control.
Apart from the actual strength of the action and barrel, there is the question of how the action could handle a catastrophic case failure. Rifles may come unglued not from fracture of the steel, but from failure of the case. Anyone handloading .303 ammunition for a LE knows that the cases much be watched carefully for incipient separations, and that a broken case tool can be very handy. Does anyone know what the situation is with .308? The higher pressures must be flexing the action/compressing the bolt more. When a .303 case separates, there is little, if any gas release. What happens with a .308? The 7.62 conversions were intended for use with NATO ball exclusively, no .308 ammunition, either handloaded or factory. If .308 cases or ammunition is used, it is a whole new ball game. The .308 No. 4 mishap reported here that resulted in a person behind the line getting a metal fragment embedded in his shoulder is an example of what can happen if a case fails catastrophically. The action held, but the extractor and case fragments became missles.
How was a .338 bullet loaded into a .303 case and fired in a No. 4 rifle?
Ackley reports throating a M1917 rifle with a .35 reamer, and firing it with .35/.30-06 (basically .35 Whelan) loads, without any sign of stress or damage. The lead core bullet sized down nicely, and passed through the .30 barrel.
- Location
- Ontario defense force (ODF HQ)
I understand what he is talking about, and I think if he's doing this one his own thats fine but will a lot of younger and/or inexperienced shooter/reloarders on this board there could be some misconception that mixing different caliber bullets might be fine with other firearms which is a big NO NO!Hitzy said:
I am fascinated by the information brought forwards by what I thought was a simple question.
The reason I put forwards the query was that 1; I have about 1500 rounds of DA 7.62 and 2; a Mk 4 sniper rifle and I was contemplating a barrel swap to use up the ammo.
At this time I think that the matching numbers sniper kit is too interesting to mess around with. Now I have to find some other gun to use the ammo with. Any suggestions?
Thank you for all of the comments,
Regards,
Maxim08
The reason I put forwards the query was that 1; I have about 1500 rounds of DA 7.62 and 2; a Mk 4 sniper rifle and I was contemplating a barrel swap to use up the ammo.
At this time I think that the matching numbers sniper kit is too interesting to mess around with. Now I have to find some other gun to use the ammo with. Any suggestions?
Thank you for all of the comments,
Regards,
Maxim08
You could probably pick up an Israeli Mauser conversion for not too much money, or even a Parker Hale sporter for not too much more. If your into semi auto's, you could consider the Norinco M-14 copy, or a Garand converted to 308.
The 308 LE conversions are becoming collectibles these days - likely more expensive than most of the above...
The 308 LE conversions are becoming collectibles these days - likely more expensive than most of the above...
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- Location
- Ontario defense force (ODF HQ)
Are you serious Bubba? Do that and you deserve a kick in the nuts with a frozen boot!!maxim08 said:
In regards to fine guns blowing unexplainable up is old news. The latest dishonerable and photographic documentation to be shown in these fine pages, is the explosive, finnish Tikka, were not only the barrel blew up, but the action as well, which split into two or more pieces. Couple of years ago, someone showed pictures of what was left of a brand new Garand, that while firing factory ball ammo, blew up. A friend of mine, witnessed a FN FALN blow up at the firing range. To the contrary, I have never, seen any pictures of a Lee-Enfield rifle that blew up under normal use with the 303 British, or 7.62 Nato ammo.
Most, if not all military bolt action long guns, uses the very best steel available in their making of the barrels and actions, and the 303 British, Lee-Enfield in no exeptions, for the simple reason, that these bolt guns are expected to performs flawlessly under the most extreme battle conditions. Looking at the battle scars of my 303 British, Lee-Enfield's, I am convinced that if there were any flaws in their metallurgy, they would have blown up long ago
In so far that the New Zealand NRA have banned the # 4 Lee-Enfield, 7.62 Nato convertions from their competitions, could also have something to do with, that although the fine Lee-Enfield rifle is more than accuarate enough for military, sniping and hunting use, it is handicaped by it's rear locking lugs, which causes it to loose out to rifles with the front locking lugs, when it comes to punching paper. This problem was recognized by the British military, which wanted to replace the 303 British, Lee-Enfield, with the front locking, P-14 Mauser clone, prior to WW1, but the dramatic miltary events of WW1, prevented this exchange.
Most, if not all military bolt action long guns, uses the very best steel available in their making of the barrels and actions, and the 303 British, Lee-Enfield in no exeptions, for the simple reason, that these bolt guns are expected to performs flawlessly under the most extreme battle conditions. Looking at the battle scars of my 303 British, Lee-Enfield's, I am convinced that if there were any flaws in their metallurgy, they would have blown up long ago
In so far that the New Zealand NRA have banned the # 4 Lee-Enfield, 7.62 Nato convertions from their competitions, could also have something to do with, that although the fine Lee-Enfield rifle is more than accuarate enough for military, sniping and hunting use, it is handicaped by it's rear locking lugs, which causes it to loose out to rifles with the front locking lugs, when it comes to punching paper. This problem was recognized by the British military, which wanted to replace the 303 British, Lee-Enfield, with the front locking, P-14 Mauser clone, prior to WW1, but the dramatic miltary events of WW1, prevented this exchange.
Snowhunter - you've obviously convinced yourself, based upon your own personal experience, that it is safe to load up an LE 303 to 308 pressures. Others have expressed concerns about doing this - in the end , its up to the individual to "sort out the wheat from the chaff".
When you state " I am convinced that if there were any flaws in their metallurgy, they would have blown up long ago" I feel you havent made the effort to get to the ultimate truth. A stock LE which has been unradiographed, would likely last indefinitely at 303 load levels. For the majority of rifles, loading to 308 would not be problematic, as you have found. However, there exists a percentage of rifles with flaws which are benign under 303 loadings, which would fail quickly, and catastrophically, under 308 pressures. Historical information about 308 conversion failures is misleading because the majority of conversions enjoyed the radiographic screen. (And you can bet the military, in their pedantic way, analysed the conversion risk ad nauseum...)
Encouraging people to do as you do is like encouraging children to play in traffic - chances are they wont get killed, but its not a good idea.
When you state " I am convinced that if there were any flaws in their metallurgy, they would have blown up long ago" I feel you havent made the effort to get to the ultimate truth. A stock LE which has been unradiographed, would likely last indefinitely at 303 load levels. For the majority of rifles, loading to 308 would not be problematic, as you have found. However, there exists a percentage of rifles with flaws which are benign under 303 loadings, which would fail quickly, and catastrophically, under 308 pressures. Historical information about 308 conversion failures is misleading because the majority of conversions enjoyed the radiographic screen. (And you can bet the military, in their pedantic way, analysed the conversion risk ad nauseum...)
Encouraging people to do as you do is like encouraging children to play in traffic - chances are they wont get killed, but its not a good idea.
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The 7.62 conversions were banned from competition in NZ because of safety concerns. There was disagreement about the ban, but it remained in effect.
The steel alloys used in Lee Enfield rifles is known, as are all the manufacturing and heat treating techniques. There is nothing magic. None of the steels used are exceptional. The alloys chosen were suitable for their intended application. There have been barrel failures in .303 rifles in the UK. These were very heavily used rifles, but there were failures nevertheless. Wartime barrels were made from forged to rough shape billets. The bars started about 14" long, were heated to forging temperature and shaped prior to being contoured and drilled. There were concerns that wartime quality control of alloy and forging temperatures may have contributed to the observed failures of .303 barrels firing Mk. VII ball.
The steel alloys used in Lee Enfield rifles is known, as are all the manufacturing and heat treating techniques. There is nothing magic. None of the steels used are exceptional. The alloys chosen were suitable for their intended application. There have been barrel failures in .303 rifles in the UK. These were very heavily used rifles, but there were failures nevertheless. Wartime barrels were made from forged to rough shape billets. The bars started about 14" long, were heated to forging temperature and shaped prior to being contoured and drilled. There were concerns that wartime quality control of alloy and forging temperatures may have contributed to the observed failures of .303 barrels firing Mk. VII ball.
cosmic and teriaq, thanks for the infomation about the possible metalurgical weaknesses of the war time production, LE 303 barrels and actions.
I might wrongly have come the conclusion, that if a LE 303 British safely can, be converted fire the 7.62 Nato, then is is also safe to reload the indentical volumed, LE 303 British case, using the 7.62 Nato reloading data, and thus avoid the costly convertion and alteration of a priced LE 303 British to the 7.62 Nato, in order to get "more bang for the buck" ?
I also find it very easy to slug the LE 303 barrels, using .44 a hard lead bullet, and then measure in inside barrel diameter it with a caliber. My various LE 303 British inside barrel diameter mesured from .306 inch to .309 inch, and thus made it, most of the time, very useful to use the plentyful .308 bullets, including the "Match King", using the 303 British or 30-40 Krag reloading data
However, I also find it important, when reloading with .308 bullets, instead of the .311 diameter, 303 bullets, for the 303 British, to exchange the .311 expander ind the 303 British, full lenght resizing dies, with a .308 expander, in order to get a firm grip on the .308 bullets.
I might wrongly have come the conclusion, that if a LE 303 British safely can, be converted fire the 7.62 Nato, then is is also safe to reload the indentical volumed, LE 303 British case, using the 7.62 Nato reloading data, and thus avoid the costly convertion and alteration of a priced LE 303 British to the 7.62 Nato, in order to get "more bang for the buck" ?
I also find it very easy to slug the LE 303 barrels, using .44 a hard lead bullet, and then measure in inside barrel diameter it with a caliber. My various LE 303 British inside barrel diameter mesured from .306 inch to .309 inch, and thus made it, most of the time, very useful to use the plentyful .308 bullets, including the "Match King", using the 303 British or 30-40 Krag reloading data
However, I also find it important, when reloading with .308 bullets, instead of the .311 diameter, 303 bullets, for the 303 British, to exchange the .311 expander ind the 303 British, full lenght resizing dies, with a .308 expander, in order to get a firm grip on the .308 bullets.
tiriaq said:
This is a really interesting post. Lots of good info here.
What do you think of the M10 No 4 mk 4 in 7.62? Seems to have been beefed up to handle it...presumably it's got the same rear lugs as the originals, thus the flex.
