Slugged an 03-A3 barrel today.

[Pirate69]

Looks like it is 0.310". Is that about what everyone else is seeing?

[T/A 6.6]

.301 X .309 on my 2 groove. Condition - like new.

[Pirate69]

T/A 6.6,
Sizing to 0.311" to 0.312"?

[chuebner]

My 4-43 03A3 slugs at .300X.309. Shot a 1 1/4" 5 shot group @ 100yd. this past Thursday using a Lyman 311299 sized @.311 over 14gr. Salut, issue sights. Gotta love that rifle.

charlie

[Pirate69]

You better believe it!!!!

[Jon K]

.2995x.308 1943 2 groove.

[RU shooter]

.309x.301 two groove

[Bob S]

There was a short time in mid-late 1942 that the groove diameter could be as high as .310" and still "pass". I have a Remington M1903 that slugs out as a full .310". However, by the time the 03A3's were coming off the production line, the groove diameter had to be between .3075" and .3095", so a .310 is out of spec. Barrels were no longer inspected with star gauges by that time, the Precision-Air gauge was used, but it is doubtfull that 100% inspection was performed. A .310 barrel in 03A3 production might be "unusual", but not unheard of. I have had bunches of NOS "spares" that slug out at .3093".

Resp'y,
Bob S.

[fatnhappy]

mine is a low serial # 1903 not 1903A3. All I use in it is cast.
Barrel is 10-11 and slugs .3015" x .310"

I have four .30 cal moulds (311290, 311041, 311284 NEI and 314299) with noses over .302 and every one of them shoots like a house on fire out of it.

http://i63.photobucket.com/albums/h152/lhsjfk3t/hunting/101_0743.jpg

[leadman]

In my 1903a3 the barrel slugs .3095", but I use a .311" boolit to fill the throat better.

You may want to try your boolit of choice in a case and see if you are able to touch the rifling.

[Char-Gar]

I have a new Remington (6-44) two groove 03A3 barrel in my Krag. I have not sluged the grooves, but the lands are .3007. We will call that .301

P.S. I went a slugged the barrel and the groove is a dead nuts .308. So we will call this barrel .301 X .308

Other than three round to testfire after the fitting to the Krag action, the barrel is unfired. The chamber is cut with a reamer ground to minimum spec, so I am guessing .309 - .310 will be what to use.

[Pirate69]

Think I need to remeasure the slug. Seems that the expected groove diameter is 0.309". I will need to polish my sizer to groove plus 0.002" in order to get a better fit. The sizer is a Lee 0.309" and gives a 0.309" bullet.

[Freightman]

My 03-A3 was .300-.308 and shoots a .310 just fine it was unfired since rebuild 1944 Remington. The man I got it from got it from the DCM a long time ago and put it in the safe never to bring it out again.