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NEW LR-308 BREAK IN ?

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Replied by AR260rem on topic Re: NEW LR-308 BREAK IN ?


OK everyone, here is the answer straight from Armalite on the nylon bore brushes and also a side question on whether Armalite will ever offer a carbine 338 Federal:

The reason for the statement of not using nylon brushes is that if used on a hot barrel they can melt inside the bore. I’m not sure why the statement in our tech notes is only for chrome lined barrels.

The .338 Federal has more of a bullet drop because of the heavier round. More dwell time in a 22” SST barrel is far better than in a 16” barrel so I doubt very much that we would offer the .338 Federal in a carbine 16” barreled configuration.

Tim Rooker
Lead Tech / CSR
ArmaLite Inc.
745 South Hanford Street
P.O. Box 299
Geneseo, Il 61254
309-944-6939 Ext 140
309-944-6949 (FAX)
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12 years 2 months ago #10544

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Replied by silverman1 on topic Re: NEW LR-308 BREAK IN ?

I will tell you about 2 Identical DPMS LR .308 That were delivered within 2 weeks of each other.
I followed the clean every shot for 10 shots with JB Bore Bright
Every 5 shots for 20 rds.
'' 10 '' " 60 ""
And have been cleaning after every shooting session.
I used LC mil surp. ammo for the break in
After bore sighting ,the first 3 rounds fired cloverleafed @ 100 yds.
I then worked a load up for 168 gr match HPBT ,and the shots make one ragged hole @ 100 yds with occasional fliers.
Another club member did not use the JB ,he just went out and started shooting.
His groups ,even though he cleaned occasionally with shooters choice copper remover ,got progressively worse.
He tried to work up a load ,and could not get under a 2 in group @ 100
He called DPMS and told them he got a BAD barrel ,and wanted it replaced .
They asked him if he broke it in ,and he never read the manual ,and claimed he never heard of it.
Anyhow ,he has been using the JB and cleaning like he should have before ,and his groups are getting under 1-1/4 in now ,and he says they are getting better.
So you can see I am a firm believer in ,micro lapping a new barrel
After about 60 or 70 rds. the patches kept getting lighter color ,and got to the point that I used the same patch for 5 or 6 cleanings.
And as far as the stainless barrels ,I think they take longer to break in than 4140 barrels do.
If you have a 16 in.barrel ,all you want to do is spray ,and pray with ,go for it ,But if you want utmost accuracy out of a barrel ,i would definately break it in.
It is a pain .breaking the rear pin out ,pulling the bolt ,put a block of wood between the reciever halves ,and cleaning ,but woorth it in the long run ,In my opinion.
11 years 9 months ago #11884

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Replied by marcus0311 on topic Re: NEW LR-308 BREAK IN ?

I always used RemOil as a cleaner/lune/protectant on my firearms. Except when I was in the MARINES. Then I used the mil-spec stuff on my M-16 and then my SAW. I've had my LR-308 AP4 for about two months now,and haven't shot it cause I just now got all the parts and tools together to install a rail kit on the f.float handguard and also strip the lower to do a laser ingraving of a cool zombie logo on the lower opposite side on the mag well of the panther logo then paint both afterwards. I didn't want to site it in then take it apart and site it in again after I complete the work on it.
Anyways, a former scout sniper told me that RemOil is a good alternative, and the complete cleaning prior to first time shooting. Then he said he would do 10 rounds slow fire keeping the barrel from getting too hot. Clean thouroughly then another 10 round slow fire and inbetween each shot run a bore snake through the barrel twice. Then do a complete thourough cleaning. After all that the rifle will be ready to be sighted in. He said that extra TLC during the sighting proccess of running a bore snake after every couple shots doesn't hurt.
This guy loves and treats his firearms like he does his own children. SOO.... this proccess might seem more involved than neccessary,but he says treating your firearms with level of TLC has never done him wrong,and when he was in the field his weapons NEVER mechanically failed him as a result. It's the proccess I'm going to follow when I FINALLY complete the custom work and take it to the range.
11 years 7 months ago #12332

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Replied by pookybear308 on topic NEW LR-308 BREAK IN ?

Man, do I ever love this site! Always get good answers & usually a variety to choose from! ;)

I just finished up installing the last bits on my DPMS pattern AR-10(clone). Time now to make a final go-round: making sure everything got tightened properly, cleaning up any trace of the build process, & lubing as needed before heading to the range for it's 'birthday celebration'.

:bow: Many thanks to all who contribute to this site & are willing to lend their time & knowledge to the noobs of the world!

-Pookybear308
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10 years 8 months ago #27296

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Replied by Sharkey on topic NEW LR-308 BREAK IN ?

Damn fine thing to see it all came together well for you PB and our members could help. We sure do have a great bunch of guys on here and we're always glad to see new members happy with their sticks AND advice.

When you hit the range, we'll also be looking forward to a solid range report and eval on the completed weapon.

God Bless man and happy shooting... :)
10 years 8 months ago #27297

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Replied by jtallen83 on topic NEW LR-308 BREAK IN ?


Thank you from those of us that couldn't help with the technical questions of a build but soaked upped all the info we could. There is no doubt sharing your build with us step by step will help me when I decide it is time for mine. Looking forward to reading your range report.
Christen it well my friend :twothumbs: :usa:
By the way, is it a he or a she?
LIBERTY FIRST!
10 years 8 months ago #27299

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Replied by pookybear308 on topic NEW LR-308 BREAK IN ?

"Christen it well my friend :twothumbs: :usa:
By the way, is it a he or a she?"

By Gawd, I don't know how to tell!!
Do I pick up the tail and count how many holes? :unsure:

:rotfl:
10 years 8 months ago #27350

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Replied by jtallen83 on topic NEW LR-308 BREAK IN ?

I think you just know after shooting them.

Mine is a she, Ethel after my great aunt Ethel who was said to be a crack shot in her younger years. I like to follow the military tradition I saw, seemed like every piece of artillery was a she. The WWII guys all made their bombers she's as well.
LIBERTY FIRST!
10 years 8 months ago #27353

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Replied by Siscowet on topic NEW LR-308 BREAK IN ?

Congrats on finishing it up Pookybear, look forward to a range report. Oh, and don't use Elle MacPherson for a christening name for your rifle, its taken already. :rotfl:
If you don't know who she is, look her up, its worth it.
10 years 8 months ago #27356

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Replied by OleCowboy on topic NEW LR-308 BREAK IN ?

There is more than one way to skin a cat: That said I follow this procedure from one of the top barrel manufs around.

www.kriegerbarrels.com/Break_In__Cleaning-c1246-wp2558.htm

"BREAK-IN & CLEANING:

With any premium barrel that has been finish lapped -- such as your Krieger Barrel --, the lay or direction of the finish is in the direction of the bullet travel, so fouling is minimal compared to a barrel with internal tooling marks. This is true of any properly finish-lapped barrel regardless of how it is rifled. If it is not finish-lapped, there will be reamer marks left in the bore that are directly across the direction of the bullet travel. This occurs even in a button-rifled barrel as the button cannot completely iron out these reamer marks.

Because the lay of the finish is in the direction of the bullet travel, very little is done to the bore during break-in, but the throat is another story. When your barrel is chambered, by necessity there are reamer marks left in the throat that are across the lands, i.e. across the direction of the bullet travel. In a new barrel they are very distinct; much like the teeth on a very fine file. When the bullet is forced into the throat, copper dust is removed from the jacket material and released into the gas which at this temperature and pressure is actually a plasma. The copper dust is vaporized in this plasma and is carried down the barrel. As the gas expands and cools, the copper comes out of suspension and is deposited in the bore. This makes it appear as if the source of the fouling is the bore when it is actually for the most part the new throat. If this copper is allowed to stay in the bore, and subsequent bullets and deposits are fired over it, copper which adheres well to itself, will build up quickly and may be difficult to remove later. So when we break in a barrel, our goal is to get the throat “polished” without allowing copper to build up in the bore. This is the reasoning for the "fire-one-shot-and-clean" procedure.

Every barrel will vary slightly in how many rounds they take to break in For example a chrome moly barrel may take longer to break in than stainless steel because it is more abrasion resistant even though it is a similar hardness. Also chrome moly has a little more of an affinity for copper than stainless steel so it will usually show a little more "color" if you are using a chemical cleaner. Rim Fire barrels can take an extremely long time to break in, sometimes requiring several hundred rounds or more. But cleaning can be lengthened to every 25-50 rounds. The break-in procedure and the cleaning procedure are really the same except for the frequency. Remember the goal is to get or keep the barrel clean while breaking in the throat with bullets being fired over it.

Finally, the best way to tell if the barrel is broken in is to observe the patches; i.e. when the fouling is reduced. This is better than some set number of cycles of "shoot and clean" as many owners report practically no fouling after the first few shots, and more break-in would be pointless. Conversely, if more is required, a set number would not address that either. Besides, cleaning is not a completely benign procedure so it should be done carefully and no more than necessary.

CLEANING:

This section on cleaning is not intended to be a detailed instruction, but rather to point out a few "do's and don'ts". Instructions furnished with bore cleaners, equipment, etc. should be followed unless they would conflict with these "do's and don'ts."

You should use a good quality one piece coated cleaning rod with a freely rotating handle and a rod guide that fits both your receiver raceway and the rod snugly. How straight and how snug? The object is to make sure the rod cannot touch the bore. With M14/M1 Garand barrels a good rod and muzzle guide set-up is especially important as all the cleaning must be done from the muzzle. Even slight damage to the barrel crown is extremely detrimental to accuracy.

There are two basic types of bore cleaners, chemical and abrasive. The chemical cleaners are usually a blend of various ingredients including oils, solvents, and ammonia (in copper solvents). The abrasive cleaners generally contain no chemical solvents and are an oil, wax, or grease base with an extremely fine abrasive such as chalk, clay, or gypsum.

We recommend the use of good quality, name brand chemical cleaners on a proper fitting patch/jag combination for your particular bore size and good quality properly sized nylon or bronze brushes.

So what is the proper way to use them? First, not all chemical cleaners are compatible with each other. Some, when used together can cause severe pitting of the barrel, even stainless steel barrels. It is fine to use two different cleaners as long as you completely dry the bore of the first cleaner from the barrel before cleaning with the second. And, of course, never mix them in the same bottle. NOTE: Some copper solvents contain a high percentage of ammonia. This makes them a great copper solvent, but if left in the bore too long, can damage/corrode the steel. Do not leave these chemicals in a bore any longer than 10-15 minutes MAXIMUM! DO NOT EVER use straight ammonia to clean a barrel.


Follow instructions on the bottle as far as soak time, etc. Always clean from the breech whenever possible, pushing the patch up to the muzzle and then back without completely exiting the muzzle. If you exit the muzzle, the rod is going to touch the bore and be dragged back in across the crown followed by the patch or brush. Try to avoid dragging items in and out of the muzzle, it will eventually cause uneven wear of the crown. Accuracy will suffer and this can lead you to believe the barrel is shot out, when in fact, it still may have a lot of serviceable life left. A barrel with a worn or damaged crown can be re-crowned and accuracy will usually return. Have the crown checked by a competent gunsmith before giving up on a barrel that may otherwise be in good condition.

This information is intended to touch on the critical areas of break-in and cleaning and is not intended as a complete, step-by-step guide or recommendation of any product. Use a quality one piece cleaning rod that is either vinyl coated or carbon fiber, a rod guide proper for the action you are cleaning, and chemicals, jag’s, patches, and brushes that you have determined work best for you. There is no “right” answer to cleaning products and equipment, however under NO circumstances should you use a stainless brush. If you choose to use brushes in your cleaning use only quality bronze phosphor brushes or nylon. Clean them after every use to extend their life. Copper solvents will dissolve a bronze brush rather quickly.


BREAK IN:

The following is a guide to "break-in" based on our experience. This is not a hard and fast rule, only a guide. Some barrel, chamber, bullet, primer, powder, pressure, velocity etc. combinations may require more cycles some less. It is a good idea to just observe what the barrel is telling you with its fouling pattern and the patches. But once it is broken in, there is no need to continue breaking it in.

Initially you should perform the shoot-one-shot-and-clean cycle for five shots. If fouling hasn't reduced, fire five more cycles and so on until fouling begins to drop off. At that point shoot three shots before cleaning and observe. If fouling is reduced, fire five shots before cleaning. Do not be alarmed if your seating depth gets longer during break in. This is typical of the “high” spots in the throat being knocked down during this procedure. It is not uncommon for throat length to grow .005”-.030” from a fresh unfired chamber during break in.

Stainless Chrome moly

5-10 one-shot cycles 5 - 25 - one-shot cycles

1 three-shot cycle 2 - three-shot cycles

1 five-shot cycle 1 - five-shot cycle"
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Last edit: 10 years 8 months ago by OleCowboy.
10 years 8 months ago #27360

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