GPR barrel break in

[keving]

I just finished putting together a GPR flintlock rifle kit. I am going to take it to the range this weekend. I have read posting on this board saying that you can not expect decent accuracy until you have about 200 rounds through the barrel. Is this true or just a commonly told myth? I cant imagine with the quality of metal and machining practices today this could be true. What gives? Thanks.

 

[Richard Allen]

I have found that new barrels seem to be more accurate after they have been shot several hundred times. It may have been that the patch smoothed out some microscopic imperfections or it may have been that I became more familiar with the new rifle or that a better load had been worked up that resulted in better accuracy. I think its a combination of all three.

I sometimes speed up the "break in" process by wrapping wrapping 0000 steel wool around a slightly under sized bronze bore brush attached to a range rod until it fits the bore pretty tightly and working it up and down the bore several hundred times. I have also lapped some bores with a soft lead slug coated with progressively finer grades of lapping compound sold for fire lapping centerfire rifle barrels.

On the other hand, some folks swear their rifles were very accurate out of the box and haven't changed over the years.

One thing I have learned is there are no absolutes when dealing with muzzleloaders. Someone else's experiences do not necessarily mirror mine. That's one of the things that makes this sport so interesting to me.

Richard/Ga.

 

[Birddog6]

I cant imagine with the quality of metal and machining practices today this could be true. What gives? Thanks.

Why ? :crackup: Mass production on a machine that does thousands of barrels ? It probably cuts, rifles, dovetails & breeches the entire barrel in under 5 min. Tho we have the technology to do almost anything, the machines are still machines & they do wear. All the barrel has to be in is Within Specs and they are not close specs... They will most likely spot check about ever 250th barrel to see if it is OK & if so the entire lot is OK. Now this is not just the GPR rifles, this is all mass produced low end priced rifles & especially ones made out of the country with cheaper labor. They cannot afford to run too close of tolerances & be able to make the barrels for the price they do them for. To do that would require the best machines & the best workers = top price for the barrels.

We are speaking of MASS production & talking about a $350 rifle that cost them about $100 Total to make........ You don't get much for that. A good comparison is a Goodoien Match Grade ML Barrel Only will cost you 2/3 of the cost of the GPR finished rifle and it is just a barrel without a breechplug .

However, for the low priced rifles the GPR rifle is, they are pretty good rifles & perform quite well & in my opinion, they ARE the best buy for the $ in a low priced mass produced rifle.

200 rounds in a ML is nothing & it will teach you the Ins & Oouts of that rifle. When you have about 3000 thru it you can say you know it Real well.... I have over 5000 thru mine & it is All original & has never failed me.

Go enjoy shooting & don't worry about breaking it in. By the time you find a load that will group about 1.5" at 100 yards off the bench, you will have the rifle broke in.

:m2c:

 

[BrownBear]

In my case it was a relative improvement. My first group at 50 yards was about 5 inches, but the second was about 3, and the third was about the same. The biggest difference seemed to be in me getting my act together rather than any change in the gun.

By about 200 shots there was a decided difference, with groups sometimes dropping to as little as an inch. I did note that while I started out with .530 balls and .015 patches, they seated a little looser by about 150 shots. Switching to .535 and .015 tightened up the seating, but also the groups.

Hard to distinguish between experience, wear-in, and changes in components. Easy to say that whatever you get at first will improve quickly. That first hundred of shots won't go as fast as the second simply because you are going to get excited and shoot more as things get better and better.

I've got about 1500 shots through my GPR now, and don't really notice any difference from the performance I was finally getting at around 200. I do notice that I'm sure enjoying shooting a lot more than I did before the GPR!

 

[Tahquamenon]

I'd say certainly you need to break in the bore. I never expect a rifle to routinely print well out of the box. Sometimes yes but more often not.

I typically shoot as quickly as I can, 20-40 conical through a new bore, followed by another 20-40 or so PRB's. Not for accuracy, just to break in the bore. Moderate loads. This also heat's the barrel to heat treat the blueing or browning. Also helps break in the lock mechanism as well.

Then srub the bore really well with a bore solvent and brushes followed by soaked patches. This will remove any leading from the conial. (I use Butch's Bore Shine)

I find that this helps get the rough machining from the bore without me having to "polish" and speeds the breaking in process.

Some folks will say "reach for the bore polishing compound right away". I don't agree and that's the last thing I would try if everything else failed.

:m2c:

 

[JOHN L. HINNANT]

Greeting Rolo T.,

Aw Shuckings.

Don't worry about it. Just go shoot your rifle and have fun.

Relax! This is all about fun and pleasure.

Take a friend with you to spot where you patches are landing. If range rules allow it, and it is safe, go pick each patch after each shot. Stack them in the order they were shot and examine each one for cutting or blow through.

If there is some patch damage, shot it for a few hundred more rounds and see if it stops.

Do not do anything other than change patch (and maybe ball size) combinations until you shoot 200-300 rounds.

Wiping with a solvent damp patch between each shot will have a gentle lapping effect on the bore also.

Relax! Go have fun. Do not get caught up in all of the negative what-if's and unknowns.

A number of problems will resolve themselves with shooting. ninety nine percent of my barrels shot from the get-go with no problems.

The rest shot problem free after 200-300 rounds.

Best regards,

John L. Hinnant