Weird Browning A-bolt 30-06 Reload COAL

[SecretSquirrel38]

I loaded up a ladder for my rifle. Set my COAL at 3.34 and they wouldn't chamber! Grabbed a factory load and it cycled properly. Measured the factory load and it measured 3.185. I don't have the tool to measure the lands so I worked backwards until they chambered smoothly at 3.20 with no resistance and they shoot and cycle. When it was 3.225 it was snug closing the bolt. Once I felt resistance I backed it out. My son Remington cycles and groups great at a COAL of 3.335. Very perplexing. I know every gun is different.

 

[huntinfool18]

Try closing the bolt on one of your resized brass with no bullet/powder/primer. There's some many things that could be causing a tight bolt. Brass that hasn't been sized properly or a primer not seated deep enough come to mind

 

[SecretSquirrel38]

Try closing the bolt on one of your resized brass with no bullet/powder/primer. There's some many things that could be causing a tight bolt. Brass that hasn't been sized properly or a primer not seated deep enough come to mind

Thanks. I checked all that. I took a load that wouldn't chamber, put in a Remington and cycled perfectly. Pretty sure it's the gun.

 

[ObiJohn]

It could be the throat... more freeborn in the Remington than in the Browning.

 

[MagnumManiac]

To check for certain, mark the top of your bullet with a sharpie all the way around the ogive, chamber and see if there are rifling marks evenly spaced where the rifling would be.
If this is the case, then your throat is short.

Cheers.

 

[FEENIX]

I loaded up a ladder for my rifle. Set my COAL at 3.34 and they wouldn't chamber! Grabbed a factory load and it cycled properly. Measured the factory load and it measured 3.185. I don't have the tool to measure the lands so I worked backwards until they chambered smoothly at 3.20 with no resistance and they shoot and cycle. When it was 3.225 it was snug closing the bolt. Once I felt resistance I backed it out. My son Remington cycles and groups great at a COAL of 3.335. Very perplexing. I know every gun is different.

Is this with a virgin brass, or has it been fire-formed from the same rifle?

 

[med358-boise]

A quick way to measure distance to the lands is a cleaning rod with a flattened jag tip or 1/4 wooden dowel. Insert the rod/dowel in the muzzle until it touches the closed bolt. Mark the rod/dowel even with the muzzle with a piece of tape, place the tape as square as possible to the muzzle just barely contacting the face of the muzzle. Repeat this process with your chosen bullet pressed into the lands (i.e. drop a bullet into the chamber and hold it in place with a pen or pencil) and mark the rod/dowel with another piece of tape at the muzzle. Measure the distance between the two leading edges of tape and you have your max COAL for that bullet given where the bullet engages the lands.

You don't mention whether the factory rounds were the same bullet as the reloaded rounds. Remember, chambers don't actually care about COAL, they care about the distance from the base of the cartridge to where the diameter of the bullet engages the lands.

The above method will allow you to determine the relating COAL when that particular bullet engages the lands.

 

[Beaver78]

I have a Browning Bar Mk2 30-06, and I had the same issue. I loaded some Sierra 165gr BTHP Gameking bullets to 3.34 and they wouldn't fit, I had to seat them deeper to get them to cycle and chamber.

 

[Chadp82]

I had a similar issue with and A-Bolt 280.

In mine I found it to be the case length. If I trimmed the cases an extra .01 they cycled fine. If I went with the SAAMI length case it was tough to close the bolt.

For bullet seating depth SAAMI and COAL were fine.

 

[SecretSquirrel38]

Is this with a virgin brass, or has it been fire-formed from the same rifle?

It is once fired, full resized brass and not fire formed Remington brass. I was shooting factory Remington Core-Lokt 165 gr. Both shot through the Browning.

 

[med358-boise]

It is once fired, full resized brass and not fire formed Remington brass. I was shooting factory Remington Core-Lokt 165 gr. Both shot through the Browning.

Were you reloading 165 Core-Lokts?

 

[Teri Anne]

I loaded up a ladder for my rifle. Set my COAL at 3.34 and they wouldn't chamber! Grabbed a factory load and it cycled properly. Measured the factory load and it measured 3.185. I don't have the tool to measure the lands so I worked backwards until they chambered smoothly at 3.20 with no resistance and they shoot and cycle. When it was 3.225 it was snug closing the bolt. Once I felt resistance I backed it out. My son Remington cycles and groups great at a COAL of 3.335. Very perplexing. I know every gun is different.

I use a RCBS Turret press these days and leave the dies set up and simply change turret heads when changing whatever I am loading. I recently noticed that my 338 Win Mag loads were having the hard to close the bolt issue, with a few completely failing to allow the bolt to close. Extraction was the same as always, and factory ammo functioned perfectly. I checked and found that the sizing die had loosened slightly and was not pushing back the shoulder as far as it needed to go. It's amazing how much a few thousandths of an inch means. A simple reset of the sizing die and all is well. What this proves is that it's easy to become complacent. Just because I worked before doesn't mean that something hasn't changed. In the old days when using the Rock Chucker press, the die settings were checked each time you changed a die. Not a bad idea even with a turret or progressive press.

 

[FEENIX]

It is once fired, full resized brass and not fire formed Remington brass.

Will these brass chamber without bullets? If so, you might have a CBTO issue and need to allow clearance with the lands.

 

[Philward]

A quick way to measure distance to the lands is a cleaning rod with a flattened jag tip or 1/4 wooden dowel. Insert the rod/dowel in the muzzle until it touches the closed bolt. Mark the rod/dowel even with the muzzle with a piece of tape, place the tape as square as possible to the muzzle just barely contacting the face of the muzzle. Repeat this process with your chosen bullet pressed into the lands (i.e. drop a bullet into the chamber and hold it in place with a pen or pencil) and mark the rod/dowel with another piece of tape at the muzzle. Measure the distance between the two leading edges of tape and you have your max COAL for that bullet given where the bullet engages the lands.

You don't mention whether the factory rounds were the same bullet as the reloaded rounds. Remember, chambers don't actually care about COAL, they care about the distance from the base of the cartridge to where the diameter of the bullet engages the lands.

The above method will allow you to determine the relating COAL when that particular bullet engages the lands.

This is my first step before loading any new bullets, I use a rod with 2 collars on it that are held in place with set screws.