.38-55 Target barrels

[Ireload2]

I noticed on another thread that Marlin is making the barrels for H&R except for the BC 45-70.
I recently got a .38-55 Target and it has the typical large bore and groove but small chamber syndrome.
The same day I bought it I got a look at a BC in 45-70 and the barrels appeared to be very similar inside - shallow rifling and a very smooth bright finish. This 38-55 barrel is exceptionally uniform. The land dia is .375. I pushed a Hornady .375 jacketed bullet through it with heavy thumb pressure and it was the same diameter all the way through with no tight or loose spots. While it is large in diameter it is much more uniform than I ever expected and it has no visible reamer marks. The only Marlin barrels I own are not of current manufacture and not good for comparison.
Is there a chance this barrel is also made by Green Mountain. My rifle serial number indicates date of manufacture is 2006.
EDG

[quickdtoo]

As far as I know, Marlin didn't start making H&R barrels until this year, the .444 being one of the first they've done. And the 45-70 BC barrel is the only one currently being sourced at GM, what it was in 2006, I don't know.

I would think that you'd have to slug the bore of your 38-55 at the muzzle and near the throat to get an accurate size of the bore, all of those I've done have been ~.0005" bigger at the muzzle compared to the chamber end, the .444 and .45 Colt Carbine barrel which were done by Marlin included, but that obviously has little affect on how accurate they are!

Tim

[handirifle]

I noticed on another thread that Marlin is making the barrels for H&R except for the BC 45-70.
I recently got a .38-55 Target and it has the typical large bore and groove but small chamber syndrome.
The same day I bought it I got a look at a BC in 45-70 and the barrels appeared to be very similar inside - shallow rifling and a very smooth bright finish. This 38-55 barrel is exceptionally uniform. The land dia is .375. I pushed a Hornady .375 jacketed bullet through it with heavy thumb pressure and it was the same diameter all the way through with no tight or loose spots. While it is large in diameter it is much more uniform than I ever expected and it has no visible reamer marks. The only Marlin barrels I own are not of current manufacture and not good for comparison.
Is there a chance this barrel is also made by Green Mountain. My rifle serial number indicates date of manufacture is 2006.
EDG

Actually .375 isn't a large bore, as the 38-55 was never designed around .375 bullets, but rather .378-.380, so it's right on par where it should be.

What I found is that when sizing the case make sure it is sized all the way with little or no roll crimp.  I use a lee Crimping die and just enough pressure to crimp the case to the bullet.  My barrel has easily taken .380 bullets.  In fact I was doing some experimenting last night and found mine would close easily with a 335gr Snover (semi pointed) cast bullet seated to a COAL of 3.130 as opposed to the normal loading of my 245gr FP cast bullet length of 2.503.  That's over 1/2" longer!  I haven't tried firing them yet but I will.

This is very similar to loadings used by BPCR shooters of the 45-70.  I have used black powder only in mine so far.

Do without the roll crimp and let us know how it goes.  also make sure the case expander doesn't open the case too far, as this might cause the same issue.

I will post a pic of thee std load and the extra long one side by side, as soon as I switch to the other computer.

[handirifle]

Here is the pic I promised.  Left is 2.503 loaded with Chey-Cast 245gr FP cast bullet, Lee crimped on the crimp groove.



Right is the 335gr Snover bullet loaded to 3.130.  The action closes but does have to be done so with a bit of authority.  It just implants the rifling on the tip of the ogive.  The crimp groove is about 1/8" above the top (third) grease groove.  There is still one grease groove in the case.  It's a long bullet.  I should be able to get about 10 more grains of powder in there, will see what it will do.

[Ireload2]

I noticed on another thread that Marlin is making the barrels for H&R except for the BC 45-70.
I recently got a .38-55 Target and it has the typical large bore and groove but small chamber syndrome.
The same day I bought it I got a look at a BC in 45-70 and the barrels appeared to be very similar inside - shallow rifling and a very smooth bright finish. This 38-55 barrel is exceptionally uniform. The land dia is .375. I pushed a Hornady .375 jacketed bullet through it with heavy thumb pressure and it was the same diameter all the way through with no tight or loose spots. While it is large in diameter it is much more uniform than I ever expected and it has no visible reamer marks. The only Marlin barrels I own are not of current manufacture and not good for comparison.
Is there a chance this barrel is also made by Green Mountain. My rifle serial number indicates date of manufacture is 2006.
EDG

Actually .375 isn't a large bore, as the 38-55 was never designed around .375 bullets, but rather .378-.380, so it's right on par where it should be.

What I found is that when sizing the case make sure it is sized all the way with little or no roll crimp.  I use a lee Crimping die and just enough pressure to crimp the case to the bullet.  My barrel has easily taken .380 bullets.  In fact I was doing some experimenting last night and found mine would close easily with a 335gr Snover (semi pointed) cast bullet seated to a COAL of 3.130 as opposed to the normal loading of my 245gr FP cast bullet length of 2.503.  That's over 1/2" longer!  I haven't tried firing them yet but I will.

This is very similar to loadings used by BPCR shooters of the 45-70.  I have used black powder only in mine so far.

Do without the roll crimp and let us know how it goes.  also make sure the case expander doesn't open the case too far, as this might cause the same issue.

I will post a pic of thee std load and the extra long one side by side, as soon as I switch to the other computer.

My cases were flared just enough to start the bullets without shaving them. The case mouths measured about .397 over the outside.
It required a hard push to get the round to clear the breech. Then they would seat when I closed it. I do not yet have a Lee factory crimp die for this round so I ran them into a .375 Win size die just enough to close the case mouth down to .395. They dropped in leaving only the rim width standing out before I close it. My next stop is the range to try these out. It appears that by the use of a crimp  I may be able to avoid messing with the chamber. I really prefer close fit chambers but not as tight as this one. My bullets measure only .379 but the bore is .380 in the grooves so I need to try bullets at .380 and .381.  I have a case neck turner that will take a .375 dowel pin as a pilot. I experimented with turning some blown out .30/30 brass and it worked fine.  If I have to I will turn the case necks with the bigger bullets. I will keep you posted on how everything goes. Have to shoot up my current supply of bullets then consider if I want to invest in a mould for this one.

It is interesting that your throat allows such long seating. My rifle engraves the bullets at 2.190 from the case head. Using the common 245 grain FN sized to .379 my AOL is 2.697.
 

[handirifle]

Do note the STYLE of bullet it lets me load long.  I haven't tried the FP bullets to see.  I only checked the longer ones to see if I could stuff more powder under them.  Looks like I might get another 8-10grains in, as a guess.

[handirifle]

It is interesting that your throat allows such long seating. My rifle engraves the bullets at 2.190 from the case head. Using the common 245 grain FN sized to .379 my AOL is 2.697.
 

Are you sure about the 2.190??  The case is that long.

[John Boy]

Here's some from my H&R rifle
Lyman   Saeco
378674   571
   
1.548   1.644 ... Chamber length measured from base of engraved bullet in the bore
1.309   1.074 ... Bullet length
   
2.857   2.718 ... Overall reload length

Actual reload length will be different depending on the case length (2.xxx or the new Starline 2.125)

Don't know the case length cut of the chamber.  If anyone has done a Cerrosafe casting ... post up the details

[Ireload2]

It is interesting that your throat allows such long seating. My rifle engraves the bullets at 2.190 from the case head. Using the common 245 grain FN sized to .379 my AOL is 2.697.
 

Are you sure about the 2.190??  The case is that long.

My recently manufactured Winchester brass is 2.080 long. The end of the engraving is .110 ahead of the case mouth.