Original barrel dimensions and muzzle wear/throat erosion

[Merc]

Questions of the day:

Where could one find the original barrel dimensions for a 1944 No. 4 Mk 1*?

How much concentric muzzle wear and jump gap distance can the No. 4 barrel sustain before it becomes inaccurate?

My No. 4 is still an accurate shooter even though it currently has a measured jump gap of .250". From what's been discussed on this forum and elsewhere, the No. 4's barrel and action were originally built to spacious specs. If true, what level of throat erosion does a .250" jump gap represent? What was the jump gap distance when it left the Savage factory? Zero?

The muzzle has a diameter of .3025". I was expecting to see a diameter of .303" which would match the caliber, not one that's actually .0005" smaller.

[Clark Howard]

Your barrel is nearly new. Both of your measurements are within new specs. Regards, Clark

[Merc]

Your barrel is nearly new. Both of your measurements are within new specs. Regards, Clark

Thank you. That's good to hear.

What do you think of a 1943 Savage No. 4 Mk 1* with a jump gap of .378"? A friend of mine is looking for a No. 4 Mk1* shooter. I may have found one for him, however, after I performed the measurement, I wasn't sure that a No. 4 with a jump gap distance of that magnitude would still be within acceptable tolerances.

[p246]

Thank you. That's good to hear.

What do you think of a 1943 Savage No. 4 Mk 1* with a jump gap of .378"? A friend of mine is looking for a No. 4 Mk1* shooter. I may have found one for him, however, after I performed the measurement, I wasn't sure that a No. 4 with a jump gap distance of that magnitude would still be within acceptable tolerances.

I have one that measures close to that, its a 1942 B.S.A. The muzzle end is still in good shape and it shoot decent groups. The velocity is not as good as my L.E.s with better bores using the same load. My nephew used it to take his first deer two years ago.

From my experience long throats effect muzzle velocity and muzzle condition/concentricity seem to have more effect on accuracy (But there is never a hard fast rule on this subject). This is on L.E. rifles with tight draws, and stocked up correctly (None are center bedded, they are in stock military condition). Seems like when I buy a rifle, even though it looks good, I always have a little buyers remorse until I put it on paper. With L.E.s I have screwed the pooch per say a few times thinking I bought a shooter but the paper says different. Good luck your mileage may vary.

[Merc]

Thanks for sharing your experiences. Muzzles can obviously stand some concentric wear and still shoot accurately. The muzzle on my No. 4 isn't worn and shoots accurately. However, the muzzle on my M1917 Winchester .30-06 does show some moderate wear. It should accept only the .3000" ring on my muzzle gauge if it was in like new condition, but it accepts the .3015" ring. It still shoots accurately so the .0015" wear must be concentric. It has a minimal (nearly un-measureable) jump gap so the velocity is probably very high since very little pressure is escaping around bullet as it moves through the gap. It would be nice to be able to predict how accurately any given rifle will shoot by simply measuring the muzzle diameter. Is there a way to tell if non-concentric muzzle wear is present without actually shooting the rifle?

[p246]

The problem is so many variables especially with Lee Enfields. Just the stocking up issues could fill pages. For instance I just found a good 42 Lithgow locally. The barrel was replaced in 43 and it didn't appear to get much use after that. Bore looked good. He let me loosen King screw and draws were nice and tight. I then looked at a 1943 Lithgow he also had, rebuilt and rebarreled in 46. Bore looked decent, loosened king screw and found a lot of movement indicating the draws were worn out or some type of draw damage. Looking at both rifles they appeared to be equals, but IF the 43 would have shot decent, which I doubt pretty soon you'd be dealing with a cracked stock. I brought the 42 home but he wouldn't move on the 43 price. It's all calculated risk. As far as I know a good eye, gauges, and if possible a bore scope are your best bet. Followed by how well the gun is stocked up. A good source of flat base new manufacture .311 and .312 FMJ bullets in some of these worn bores would help to.

Good luck the hunt can be fun or an ass kicker....

[JB White]

Merc, this is a battle rifle intended for minute of man, not minute of angle. Mass produced using mass produced ammo. All from various makers and subcontractors. Specifications are merely within acceptable parameters to maintain reliability in combat.
Sandbagged specifications for target accuracy don't exist. Either it shoots very well or simply well enough.
If you by chance happen across a good one or a great one, consider yourself lucky.

You could always opt to build up a new one using a Criterion barrel ordered to your specs.... if they offer that option.

[p246]

Merc, this is a battle rifle intended for minute of man, not minute of angle. Mass produced using mass produced ammo. All from various makers and subcontractors. Specifications are merely within acceptable parameters to maintain reliability in combat.
Sandbagged specifications for target accuracy don't exist. Either it shoots very well or simply well enough.
If you by chance happen across a good one or a great one, consider yourself lucky.

You could always opt to build up a new one using a Criterion barrel ordered to your specs.... if they offer that option.

Yep you can stil get No 4 barrels in original 303 or you can order them with 308 sized bores so one has better bullet options. It's pricey though, I think one would be better off finding a nice No 4 Mark II. When I looked into it looked like 5 bills by the time the smith was paid.

May not be a TAAc drivers but the mad minute is a lot of fun...especially with creme puff loads

[Merc]

P246 & JB,

Great advice as usual.

I'm not really looking for anything specific right now for myself, but you never know - something could develop at the next gun show, etc. I'm satisfied with the rifles I own and consider myself lucky that they're all great shooters considering their age and origins. I'm just trying to understand how wear affects accuracy and what the limits of wear are before rifles become inaccurate or unsafe to shoot.

Someone from out-of-state asked me to be on the look-out for a safe shooting No. 4 Mk 1* that likely saw WW2 service. I have several possible sources who might be able to produce such a rifle but I won't point him towards anything without at least checking for possible problems. I say this knowing from my own experiences that you have to be lucky to find a rifle that passes all the measurements and tests and can still shoot accurately and consistently. I obviously won't be able to take any of them them to the range to test fire, which is the ultimate test, so eyeballing is all I can do. Unfortunately, it's like buying an old used car without ever starting the engine.

[PhillipM]

Yep you can stil get No 4 barrels in original 303 or you can order them with 308 sized bores so one has better bullet options. It's pricey though, I think one would be better off finding a nice No 4 Mark II. When I looked into it looked like 5 bills by the time the smith was paid.

May not be a TAAc drivers but the mad minute is a lot of fun...especially with creme puff loads

A 30/303? What a great idea!

I don't mess with foreign rifles much, but was chewing the fat with a buddy that does the other day and he remarked the US was the only country to develop 308 bore ammo. How come?

[p246]

A 30/303? What a great idea!

I don't mess with foreign rifles much, but was chewing the fat with a buddy that does the other day and he remarked the US was the only country to develop 308 bore ammo. How come?

That topic comes up from time to time with a friend whose strictly a collector but much older than I. His theory is the young nation moving up wanted to be a little different. When .311 was so popular why .308. There's got to be an ordnance study or a US 30 cal expert who knows the given reason by the government.

[p246]

P246 & JB,

Great advice as usual.

I'm not really looking for anything specific right now for myself, but you never know - something could develop at the next gun show, etc. I'm satisfied with the rifles I own and consider myself lucky that they're all great shooters considering their age and origins. I'm just trying to understand how wear affects accuracy and what the limits of wear are before rifles become inaccurate or unsafe to shoot.

Someone from out-of-state asked me to be on the look-out for a safe shooting No. 4 Mk 1* that likely saw WW2 service. I have several possible sources who might be able to produce such a rifle but I won't point him towards anything without at least checking for possible problems. I say this knowing from my own experiences that you have to be lucky to find a rifle that passes all the measurements and tests and can still shoot accurately and consistently. I obviously won't be able to take any of them them to the range to test fire, which is the ultimate test, so eyeballing is all I can do. Unfortunately, it's like buying an old used car without ever starting the engine.

Good analogy at the end. I know where a 45 LongBranch is that might be coming up for sale. I believe it was rebuilt by our northern neighbors in 1950. The bore looked good and the stock was tight. The guy would let me shoot it if I asked. If that flavor is on your friends table let me know. It does have the 300\600 L shaped flip sight which some people don't prefer. I could at least shoot a group of Privi and a group of MarkVii pulled bullets over 39 grains of Varget. If it will shoot both those it should be good. Let me know as any excuse to shoot is actually a reason. FYI I'd be interested but already have a nice 45 Longbranch example.

[Merc]

Good analogy at the end. I know where a 45 LongBranch is that might be coming up for sale. I believe it was rebuilt by our northern neighbors in 1950. The bore looked good and the stock was tight. The guy would let me shoot it if I asked. If that flavor is on your friends table let me know. It does have the 300\600 L shaped flip sight which some people don't prefer. I could at least shoot a group of Privi and a group of MarkVii pulled bullets over 39 grains of Varget. If it will shoot both those it should be good. Let me know as any excuse to shoot is actually a reason. FYI I'd be interested but already have a nice 45 Longbranch example.

I just emailed him and he will let you know.

My 1944 No. 4 Mk 1* has some stampings on the metal wrist band that has me wondering. The serial number is there and right above it is "51" and "K." Below the serial number is the letter "B" which also appears on the rear sight and adjustment knob. Since many of the No. 4s were rebuilt after the war, is the "51" the 1951 rebuild date and the "K" the inspector? Is the "B" also an inspector's mark? The broad arrow and crown proof symbols are also present on a few parts.

[Merc]

Good analogy at the end. I know where a 45 LongBranch is that might be coming up for sale. I believe it was rebuilt by our northern neighbors in 1950. The bore looked good and the stock was tight. The guy would let me shoot it if I asked. If that flavor is on your friends table let me know. It does have the 300\600 L shaped flip sight which some people don't prefer. I could at least shoot a group of Privi and a group of MarkVii pulled bullets over 39 grains of Varget. If it will shoot both those it should be good. Let me know as any excuse to shoot is actually a reason. FYI I'd be interested but already have a nice 45 Longbranch example.

He's looking for a British-made No. 4 that was made during WW2. His goal is to acquire a WW2 military rifle from each of the major participants. I will start attending the numerous western PA gun shows next month and hopefully will find one for him.

I always look at the gun show WW2 No. 4s that are for sale just to compare condition and price. I would say that most have been the Savage-made No. 4 Mk 1* rifles which surprises me since so many of the Long Branch and British versions were also made.

[JB White]

Not too surprising given that Savage made much more No4 rifles than any other maker ;)

[p246]

He's looking for a British-made No. 4 that was made during WW2. His goal is to acquire a WW2 military rifle from each of the major participants. I will start attending the numerous western PA gun shows next month and hopefully will find one for him.

I always look at the gun show WW2 No. 4s that are for sale just to compare condition and price. I would say that most have been the Savage-made No. 4 Mk 1* rifles which surprises me since so many of the Long Branch and British versions were also made.

Savage and Long Branch did not have to endure the early to mid war bombings that England had to. Reason British " dispersal rifles" were built. BSA Shirley factory was bombed. Only Brit factory still making No. 1s. Dispersed salvaged equipment to other smaller factories to continue production. If memory served the wood furniture equipment was destroyed and they imported Lithgow furniture. I'd have to thumb through Skinnertons book to make sure but that's what memory seems to recall.

[Merc]

But still, you'd think a few British WW2 versions would show up at gun shows now and then. I can only remember seeing one Long Branch and zero British No. 4s over the past year or so. Of course, all that could change at the next show.

[p246]

Mainly here (Midwest) it's Savage and Longbrach followed by Lithgows and Isshys. Brits are out there in No 4s but not as common. It took me a while to find a good early BSA. Found a lot of worn rifles along the way. Jump back to WW1 I find mostly Brits and occasionally a Lithgow.

[Merc]

Questions of the day:

Where could one find the original barrel dimensions for a 1944 No. 4 Mk 1*?

How much concentric muzzle wear and jump gap distance can the No. 4 barrel sustain before it becomes inaccurate?

My No. 4 is still an accurate shooter even though it currently has a measured jump gap of .250". From what's been discussed on this forum and elsewhere, the No. 4's barrel and action were originally built to spacious specs. If true, what level of throat erosion does a .250" jump gap represent? What was the jump gap distance when it left the Savage factory? Zero?

The muzzle has a diameter of .3025". I was expecting to see a diameter of .303" which would match the caliber, not one that's actually .0005" smaller.

Notes from a gun show I attended in Monroeville (near Pittsburgh) last Sunday:

A vendor had a nicely dressed up No. 4 Mk 1* Savage for sale with a bayonet and scabbard. It looked as if the stock, hand guards and external hardware had been replaced. In addition to my bore light, I always bring my headspace, muzzle erosion and jump gap gauges with me to these shows, just in case. Always being curious, I inserted my muzzle erosion gauge into the muzzle. To my utter amazement, it disappeared down into the bore completely and I had a heck of a time retrieving it. The vendor obviously never checked the condition of the barrel before putting all that time, effort and money into making the rifle look new-ish. It pays to bring your light and gauges to these shows if you're thinking about buying a rifle.

[Johnny P]

In the 1903 Springfield barrel the nominal bore diameter was .300 and .308 groove diameter. Manufacturing tolerances allowed a bore diameter of .2995 to .3015, and a groove diameter of .3075 to .3095. Going from one end of the tolerance to the other is going to skew the results with a breech bore gage even though both barrels are new.

I have an original August of 1940 M1 Rifle with the original barrel that reads 1.5 on the breech bore gage, while a new never installed Springfield Armory 1-52 barrel reads 2.5 on the same gage.

[Sunray]

There's no such thing as a "jump gap " measurement. There is a throat erosion though. However, a .30 calibre throat erosion gauge will tell you nothing about a .303 Brit chamber.
Dunno if you'll be able to get to this, but it's a BILINGUAL CF manual.
http://photos.imageevent.com/badgerdog/generalstorage/edhortonmanuals/2002%20No.4%20Data%20Summary.pdf
The .303 British headspaces on the rim. Military spec Max OAL is 3.040". Accuracy depends on the diameter of the bullet vs the groove diameter. Most commercial ammo and bullet makers use .311" or .312"(Montana Bullet makes some larger diameter cast bullets). Accuracy will be poor if you use the wrong diameter bullet(like a .308" bullet) in an oversize barrel.
Any No. 4 Mk 1* still around is highly unlikely to have seen any W.W. 2 service. No. 4 was in use up here with Army Cadet Corps until the mid 90's, as I recall. Still used as DP rifles with colour parties.
All remaining Savage made rifles, parts and machinery got sent to Long Branch when the contract expired. Had one on my MIU long ago.
Lithgow Lee-Enfields are NOT No. 4's. They're No. 1 Mk III's. Aussies didn't use No. 4's. Ishapore didn't make 'em either.
"...original 303..." That was the bore diameter. Groove diameters were .311" to .315", even at Long Branch.
You used to be able to order a Criterion No. 4 Rifle barrel chambered in .308Win. It is not a .308" barrel chambered as a .303 Brit. No longer available.

[JB White]

There's no such thing as a "jump gap " measurement. There is a throat erosion though. However, a .30 calibre throat erosion gauge will tell you nothing about a .303 Brit chamber.
Dunno if you'll be able to get to this, but it's a BILINGUAL CF manual.
http://photos.imageevent.com/badgerdog/generalstorage/edhortonmanuals/2002%20No.4%20Data%20Summary.pdf
The .303 British headspaces on the rim. Military spec Max OAL is 3.040". Accuracy depends on the diameter of the bullet vs the groove diameter. Most commercial ammo and bullet makers use .311" or .312"(Montana Bullet makes some larger diameter cast bullets). Accuracy will be poor if you use the wrong diameter bullet(like a .308" bullet) in an oversize barrel.
Any No. 4 Mk 1* still around is highly unlikely to have seen any W.W. 2 service. No. 4 was in use up here with Army Cadet Corps until the mid 90's, as I recall. Still used as DP rifles with colour parties.
All remaining Savage made rifles, parts and machinery got sent to Long Branch when the contract expired. Had one on my MIU long ago.
Lithgow Lee-Enfields are NOT No. 4's. They're No. 1 Mk III's. Aussies didn't use No. 4's. Ishapore didn't make 'em either.
"...original 303..." That was the bore diameter. Groove diameters were .311" to .315", even at Long Branch.
You used to be able to order a Criterion No. 4 Rifle barrel chambered in .308Win. It is not a .308" barrel chambered as a .303 Brit. No longer available.

Have you been mixing your meds with hooch again?
Nobody made any claim about Lithgows, Ishys, BSA dispersals being No4's. Only what was available on certain regional markets.
The "jump gap" being referred to is the Leade/Small cone. He used revolver slang...so, what?
Criterion did/does offer replacement No4 barrels. (I haven't looked in the past few months)


Any No. 4 Mk 1* still around is highly unlikely to have seen any W.W. 2 service.

What planet are you shopping on???

[bigedp51]

Questions of the day:

Where could one find the original barrel dimensions for a 1944 No. 4 Mk 1*?

How much concentric muzzle wear and jump gap distance can the No. 4 barrel sustain before it becomes inaccurate?

My No. 4 is still an accurate shooter even though it currently has a measured jump gap of .250". From what's been discussed on this forum and elsewhere, the No. 4's barrel and action were originally built to spacious specs. If true, what level of throat erosion does a .250" jump gap represent? What was the jump gap distance when it left the Savage factory? Zero?

The muzzle has a diameter of .3025". I was expecting to see a diameter of .303" which would match the caliber, not one that's actually .0005" smaller.

Weatherby Rifles are known for having long throats, a AR15 rifle has a throat twice as long as most .223 rifles. My Savage .223 with a 1 in 9 twist has a longer throat than my AR15 rifles.

A used Enfield rifle will have Cordite throat erosion and as long as the rifle met accuracy standards it was kept in service.

If the rifle looks in good shape and the muzzle is OK then buy the rifle and shoot flat base bullets.

Below is a 10 shot group fired at 50 yards from a well worn 1943 No.4 Enfield after making bedding adjustments to the rifles fore end. After this the sights were adjusted for 100 yards, and with a PH-5C target sight I could keep 5 rounds in the X ring at 50 yards.

http://www.milsurps.com/images/imported/2010/05/rangedaytarget-1.jpg

And below is the best group fired at 50 yards with the same Enfield out of five targets before doing anything to the loose fore end. Some of these targets only had two bullet holes in the target because of bedding problems and not having the required 2 to 7 pounds of up pressure at the fore end tip.

http://www.milsurps.com/images/imported/2010/05/looseforend-1.jpg

Bottom line, the two best groups I have ever fired with a peep sight were with old worn military rifles and now rival what my older eyes can now do with a scoped rifle.

[Merc]

Weatherby Rifles are known for having long throats, a AR15 rifle has a throat twice as long as most .223 rifles. My Savage .223 with a 1 in 9 twist has a longer throat than my AR15 rifles.

A used Enfield rifle will have Cordite throat erosion and as long as the rifle met accuracy standards it was kept in service.

If the rifle looks in good shape and the muzzle is OK then buy the rifle and shoot flat base bullets.

Below is a 10 shot group fired at 50 yards from a well worn 1943 No.4 Enfield after making bedding adjustments to the rifles fore end. After this the sights were adjusted for 100 yards, and with a PH-5C target sight I could keep 5 rounds in the X ring at 50 yards.

http://www.milsurps.com/images/imported/2010/05/rangedaytarget-1.jpg

And below is the best group fired at 50 yards with the same Enfield out of five targets before doing anything to the loose fore end. Some of these targets only had two bullet holes in the target because of bedding problems and not having the required 2 to 7 pounds of up pressure at the fore end tip.

http://www.milsurps.com/images/imported/2010/05/looseforend-1.jpg

Bottom line, the two best groups I have ever fired with a peep sight were with old worn military rifles and now rival what my older eyes can now do with a scoped rifle.

The original sights on my 1944 No. 4 Mk 1* are surprisingly accurate. I mounted a Bushnell scope on it for a while and found that I could shoot just as well at 100 yards with the ladder sight at its lowest setting. This was after I figured out the front blade needed some minor adjustments. With the ladder sight folded down and aiming through the peep sight, the groups are about 6 inches high at 100 yards.