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Discussion Starter · #1 ·
Basically to understand the problem is the beginning. Then to correct the problem and third to keep the problem from returning.

The biggest enemy (besides some politicians) we face is carbon be it in barrel or cartridge case. I have been doing a goodly amount of testing the last three years and I have now proven to myself that I have wasted some awfully good barrels over the years by my cleaning methods not being effective as I perceived them to be.

The best bumper sticker I have ever read said:"IF YOU THINK EDUCATION IS EXPENSIVE, TRY IGNORANCE"


About seven years back (doesn’t seem that long) a friend brought me a 700 Police Sniper with stainless barrel that was almost new. At 600 rounds the barrel was gone. I cut threads and set it back and rechambered with a short throat tight 308 reamer I had made up and he went back to the party. He got 1100 rounds that run before it went. Cut it in half and no rifling ½ in front of chamber.

This guy and another friend are 50/60 vintage and one had a 600 yard range next to his house and these guys got together about six evenings a week year round and fired off 20 to 40 rounds. My friend with the Police Sniper would fire three to five shots and let it cool and another 3 to 5 over a two to three hour period. My other friend had a Chandler Sniper Rifle and he had 10,000 rounds on that barrel at that time and it was still driving them. The difference was the friend with the Chandler was shooting all his while the barrel was warm and immediately cleaning his barrel with bronze brush first and then put it away.

That got me to thinking, our test barrels used for ammo acceptance went 15,000 to 17,000 rounds before they went out of spec. As highpower shooters we think we have done great things with a barrel if we get 5000 rounds. Well think of this way, most chome moly barrels are 4140 and if test barrels and highpower barrels are same steel why then did the high-power barrel fail?

As highpower shooters how many guys do you see cleaning their barrels before they leave each firing line moving back? I know some guys that will clean before 600 but most of us don’t clean until we finish for the day. I believe that is what is killing us, we are allowing the barrels to remain fouled the entire day.

Then it hit me. Only took 35 years but OK I am slow. The difference in the gov’t test barrels is they are only fired a few rounds and cleaned. Ammo tests are conducted as follows:

Three accuracy rigs are taken to range with their log books. Each rifle is placed in a “vice” we called Frankford Arsenal Mounts or hard mounts and one shot is fired at 600 yards. Guy in pits radios back and tells the gunner where he hit and he adjusts the wheels to center the group on a large sheet of blank paper. Ok he generally fires three rounds to get it on and when he is there the pit guy radios back to run the string.

The gunner loads five rounds in mag and has 5 rounds in hand while at the same time the pit man has pulled and pasted the target. The gunner then fires all ten rounds as fast as he can operate the bolt (generally these were 1903 actions) to get all rounds in same wind condition. A good gunner will cycle 10 rounds in 15 seconds since there is no aiming and the mount returns to original condition on firing.

Pit man will pull target and measure the group. If it is in acceptance accuracy he radios the measurement and changes the paper while the gunner removes the rifle from hard mount, records the rounds fired in barrel log and replaces rifle 1 with rifle 2 and repeats the scenario. Same thing for rifle three.

If one of the groups is not acceptable he then has target changed and he fires a group with Reference Ammo which is a special lot known to produce acceptable groups with good barrels. If the group with Reference ammo is not acceptable they deadline the rifle and go get another. If the Reference ammo group is within spec they will retest one time with the lot up for acceptance. If it passes fine, if not the lot is rejected.


I set out to run some experiments to determine the contributing factors based on the above. Three years ago or four (I have CRS) I got a new 700 Remmy 308 for the action and I figure OK I have this thin 22” barrel brand new, lets see if I can extend the life.

First I measured the throat with an erosion gage.

Note: To save lots of writing go to:
<!-- m -->http://www.beastwerks.com/Throat_Erosion_Gauge.htm<!-- m --> which will explain what these are for and how they are used.

Next I examined the chamber neck/throat area with a bore scope. I have Olympus Series 5 7MM 30 degree and it is marvelous for 7MM and up tubes. I made notes of things I saw such as reamer marks in forcing cone etc.

I have a goodly number of 173 pulls so that was to be my test bullet with 4895 mainly.

I started shooting it and cleaning every 12 rounds or so and I had 50 dedicated IMI cases that were recycled through this rifle time and again. First loading was IMI factory with 180 grain Sierra BT hunting bullets.

I fired the 50, cleaned the barrel and immediately reloaded the ammo and a very strange event happened. The primer pocket residue was quite soft and fell out almost as a powder. First I thought the IMI boys had a different primer mix but read on, as it turns out they did not. Next I borescoped the barrel again and took erosion readings every so often.

At 8 rounds erosion gage showed 8 ½ rings, at 100 rounds 10 ½ rings, at 150 rounds top of 11th ring and then it stopped. The reason for the rapid advancement is the raised metal on rifling left over and from the reamer marks being blown away.

OK I had 11 rings at 150 rounds, 11 rings at 250 rounds, 11 rings at 350 rounds, bottom of 11th ring at 529 rounds, 754 rings bottom of 11th ring. Note the 11th ring is about .015 wide and the other rings are centered every .100”. (Note: testing at APG many years ago determined the wear rate on 30 cal rifle barrels normally advanced at .100 per 1000 rounds. This is the reason the Garand/M14 gages have .100” separations between rings.
Otto Haenel was Test Director on that test and he told me he took 10 new M1s and a 2 ½ Ton GI truck full of ammo and after initial measurements fired 1000 rounds on each rifle and then took the barrels to metrology for measurement. The testing was stopped when the barrels reached rejection criteria which is about 8 to 9 inches at 100 yards depending on whether it was M1 or M14.

Borescoping during this series was amazing in that when I got my bore scope I looked at every bolt gun I have and made notes of throat condition as compared to the number of rounds. I already knew that on most of my tubes on my target guns (308/30.06) the reamer marks are generally gone at end of the first HP match or two which with zeros is about 200 rounds of course.

Now I have a barrel at 754 rounds that has been cleaned very frequently and I still have reamer marks ! ! ! Now it is a given that the 22” sporter barrels were shall we say did not have a high life expectancy from the accuracy standpoint but here I have one that is going strong.

Quick side note: At this same time frame I found a Sears Mod 53 (Mod 670 Winchester basically in 30.06) and I did the same procedures and had it up to 500 rounds and the throat condition was the same. Basically I had similar conditions in 308 and 30.06 with frequent cleanings.

Back to the Remmy 308 saga. I decided to see what a hot schedule would produce. I had upped the number of shots to 22 round strings between cleanings and taken barrel temps. Depending on ambient temp the barrel temp taken 3” from muzzle gave 122 to 126F shooting 22 rounds in about 12 minutes to 14 minutes which is what is normally takes me at 600. I upped the firings schedule to about a 8 min minute string and barrel temp went to 165F. Bore scope and erosion gage showed no change. Next I shot a string in maybe four minutes and barrel temp went to 190F at the muzzle!

This time I recorded movement on the erosion gage. I had noted a little heat checking around 650 that took a 30X borescope to see and it was progressing slowly. At 900 rounds I was just below 11th ring. At 1009 rounds the last trace of the reamer marks were gone, I was still just below 11th ring and pulled the barrel off and rechambed with 7/08 heavy barrel I know call the Confederate Swamp Gun. It is a swamp cut Pacnor barrel about 23 ½ inches that was originally chambered in 280 Remington and had about 3500 rounds on it. A friend pulled it off and gave it to me.

OK lets go back a bit, during my initial borescope sessions with my bolt guns I saw a horrible condition. Gouges about ¾” long in the throat area. Only thing I could figure was dirty ammo and if I drop ammo I take great pains to clean it off and I really could not fathom what was happening and why then the little Remmy 700 gave me the answer.

After one firing session at the 250 round point I did something different, I did not reload the ammo immediately but put it on bench and loaded it a week later and the primer residue was nice and hard as I was used to finding. Next I borescoped the barrel and I have a identical gouge I saw on my other bolt guns.

This ammo had gone from the loading tray to CaseGard box to gun and back in box and back to loading tray and the cases didn’t even touch the bench. It didn’t take long to figure out it was the primer residue dropping through the flash hole when I cleaned cases and it stuck to the carbon on inside of case. On firing it got up into throat and was laying there waiting for the next round to embed it in bullet jacket and start engraving the barrel.

I then read where Mitch Maxberry had concluded primer residue was doing the same to his guns.

Next I had a nice conversation with a PhD. Chemical Engineer and asked him about the formation of carbon and what happens. He confirmed it does get hard when it cools down but had never seen a study to determine hardness against time.

Now everyone that reloads has noticed on some ammo when the expander ball is pulled back through the neck the amount of force goes up tremendously and on cases that have not had the necks scrubbed the force is enough to almost lift the loading table. Obviously this is not helping the neck and stretching follows.

Pull you FL dies down, wipe off the expander button and see if you have any scoring on your expander ball. Bet you do. Now think of this, what caused it? What is put in steel to harden it? Carbon. A brass case is not hard enough to score hardened steel expander ball but embedded carbon inside the case mouth sure is.

I now thoroughly clean my case necks, size them without expander ball and then on a separate operation I run a expander mandrel in from the top and expand it to where I have .001 to .0015 grip on my long range ammo.

To aide in case neck cleaning I take Q tips and ER to the range. Immediately after firing I just wet a Q tip and wipe around the inside of the case mouths and this does two things. It removes massive amounts of carbon from the case neck and what it doesn't remove will keep it soft till you can clean them better. You will be impressed in just how much carbon a Q tip will remove and it will make you wonder of just how much is still down inside the case body waiting to be deposited in your barrel the next time you shoot after it has hardened up.

A lot of folks judge the quality of their ammo by the amount of seating force. Uniformity of velocity is directly related to BULLET PULL forces and not bullet seating forces. MIL SPEC on M118 Long range has a minimum bullet pull of 10 lbs. Ball ammo has a min pull of 45 pounds. THERE IS NO MAXIMUM BULLET PULL SPECED ! ! ! !

Want a shocker, pull down a box of M118 Match and measure the amount of force required to unseat bullets with a Force Gage. It is not uncommon per ammo engineers to see a bullet pull of 300 POUNDS. Anybody want to bet a variation of 10 lbs to 300 lbs won’t cause trouble in River City?

I measured the amount of force my Hollywood loading tool produced in an effort to check bullet pull. I used two force gages. I sent one up to measure the amount of down force in pounds and the other to measure the amount of force applied to the handle. If I remember correctly the pull force was about 6 ½ times higher than the handle force so 10 pounds of handle force is 65 pounds of pull and I have had M118 want to lift my loading table off the floor and with what is on it is several hundred pounds.

It wouldn’t hurt to invest in a force gage. They are on ebay for a fraction of what they sell for new. I would get no less than a 50 lb gage and better yet a hundred pound. The electronic gages will measure and record the highest force delivered during a cycle and are very nifty.

Carbon in the case neck will grip the bullet by differing degrees, clean out that carbon and you will find you have a much more uniform bullet pull.

Food for thought. Check Sierra ballistic tables for 30 cal match bullets at 1000 yards. Say 2700 fps and then check 2600 feet per second and 2800 feet per second and see what the difference is in bullet drop. OK if your extreme velocity spread is 50 feet per second and you know the bullet will drop 40 inches with 100 feet velocity change then you know you are looking at 20 inches of vertical dispersion before you add in sight error, heart beat, mirage, wind, etc.

You want long range ammo to have an extreme spread of 25 fps or less if you expect to stay anywhere near the X ring. Otherwise you have done it to yourself to show up with a combination that won’t do it.

Oh by the way I have chronographed M118 and 60 feet per second variance between rounds is about average. I have seen it at like 80 feet per second. Anyone want to go to 1000 yards with ammo shooting 36” of elevation?

Bottom line guys, clean your barrels often, clean your brass every time, clean your primer pockets making sure no carbon goes though flash hole as CARBON IS THE ENEMY right behind anti gun politicians.
 

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The Hog Whisperer (Administrator)
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I took the liberty of breaking this excellent post by Humpy out of another thread. Humpy, thanks again.
 

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That's why a drill stays next to my loading bench.

I use nylon bristle brushes the size needed, mounted in the drill. I wrap the brush with 0000 steel wool and lightly polish the inside of the necks everytime I load. I make a shoulder of steel wool near the back of the brush so it polishes the chamfer and top of the neck. I want the bullet to slide in very smoothly and when I pull a bullet from a case, I don't want to see ANY scratches or signs of it having ever been seated in a cartridge. It had better still look brand new.

I also mount my primer pocket uniformer in the drill and use that to clean the pockets every time. It also works good as a pressure indicator. If you are taking fresh metal out, that means you either didn't get it right the first time or you are over pressuring the case. Since I know I got it right the first time, I know my pressure's were a little high on that load.

Then there are a few other things that many would say are time wasted, but it's my time and for some reason, I seem to shoot little bitty groups most of the time.
 

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Outstanding post Humpy. One question, is ER the bore cleaning stuff that is mentioned in Gunsmith Kinks from Brownell's and do you clean your barrels with it. I just found out about it as I read the monthly news letter from frank. Thanks again, Lou
 

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Discussion Starter · #9 · (Edited)
Yes ER is the same or rather close to it. I don't put the acetone in the stuff I make. Just Mercon Dexron, K1 Kero and mineral spirits. I make it 1.5 gal at a time.

I just posted another thread of a rethink based on something I just did. Look up a thread called The Carbon War Chronicles. I just found it: http://shootersforum.com/showthread.htm?t=73465&highlight=carbon+war+chronicles


Be assured I still love ER but this is going to be what I will be using for a while. I have had nothing but positive results with it. I guess I have given away ten gallons of the stuff in jars to friends who also love it. It is also great for fire ants ! ! ! ! ! !
 

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Thanks Humpy, I am almost to the point of feeling sorry for the fire ants!! Lou
 

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Discussion Starter · #11 ·
LR Shooter, yeah them fire ants have a number done on them when I spray the mound or rather the ants on the mound and let them take it back to the queen. Best stuff I ever found for fire ants.

Went to a practice session today at Ft. Gordon and we fire three strings at 600 yards.

I could not be happier. First string I fired 22 rounds and headed for the car immediately and laid the Mobil 1 to a bronze brush for 15 passes just to open the bidding. It cleaned right up and next match I used same load but changed bullets from 173 to 175 Sierra MKs. Again it cleaned up just fine. Both these loads were with 4895 (30.06). Scores were 194, 194 and 192. First two strings sun was behind targets so a big aperture used for a frame hold. Last string I could see better and it was one of those days when you were in you were really in and when you were out you were really out.

So I got caught a couple of times with a switching headwind and that got me a 8 and a 7 right there. I did catch one switch and saw it coming and cranked on 1 2/3rds MOA wind and let it fly and hung a 10 at 3:00. I should have cranked on 2 1/3 MOA. One of the 9s was me. I called it a 9 at 1:30 and that is exactly where it came up. I had three flags to look at blowing from behind targets toward the line. Two flags would blow towards 5:00 and one towards 7:00 at same time.

For the third string I had 54.5 gr. WC852 with 180 Sierra MKs and that propellant was somewhat harder to clean up. Took three 15 pass sessions to break it all loose.

When I got home I went out and deprimed them the FL sized them and have them tumbling now.

I checked bullet seat length which is arrived at by soft seating a bullet and chambering it and letting the barrel throat place the bullet where it wants it so when I open the bolt I know exactly where the barrel "placed" it.

Barrel set back job now has 226 rounds and OAL is still the same. OAL is still under 3.300 so until the throat gets burned a bit the OAL won't change. One this positive though, if the throat doesn't move forward fast the longer the barrel will run before it needs another set back.

Normally on barrels I have chambered with this reamer it takes about 500 to 700 rounds before the throat will take a factory length round without engraving the bullet.

I will know more when I have 500 rounds on it which shouldn't take that long to arrive at.

It was about 96F out there today to boot.
 

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Discussion Starter · #12 · (Edited)
More info:

At the 600 yard practice match on Saturday I tried three different loads with three different bullets and two propellants.

With the 4895 the clean up was as normal. 15 passes with wet bronze brush immediately aftering firing followed by patches and another five passes with bronze brush.

The last load was using WC852 (milsurp ball) and it was harder to clean. I initially did 15 passes followed by 5. To get the last of it I did another 10 passes and got it out.

In the muzzle extension the carbon from 4895 came out easily. The WC852 took out about 95% of it immediatley but I did not have anything to get to the very edge that would not scratch the muzzle so I left it wet till I got home and a bronze pin took it right out.

I ran the erosion gage in and it showed I have a movement of about 3/4s of a ring so I figured I would have to change seat depth. Normally on a new chamber job I have about 1 to 1.5 rings of movement in first 100 to 150 rounds.

I arrive at seat depth by soft seating a bullet longer than I had previously and closing the bolt and let the throat put the bullet where it wants it. To my great surprise the seat depth at 226 rounds is the same as it was at 0 rounds ! ! ! The reamer I cut this with gives me a short throat so OAL with 173 bullets is 3.297" and normal 30.06 chamber is 3.340".




I had another surprise as well. I borescoped it and there was absolutley no copper in barrel as far as I could see in front of chamber which is about 6 inches. I ran bore scope in front end and it was copper to XXXX and gone last 16" of barrel with build ups six inches from muzzle. I had never defouled it and at 160 rounds with was still shooting well at 300 yards. During the first strng I had a massive zero shift vertical at the 12th round and had to come down 1.5 MOA to get centered again and it stayed there. This barrel is a tight bore and and a .2984 plug will not enter muzzle. Note:: LC 173 match bullets run large and spec .308 to .3089 with hard jackets.

So I laid the Mothers to it and it took it right out quickly. 3 patches of it was all it needed and copper was gone.

Loaded up another 200 rounds for it yesterday but will lay the Mothers to it after every match from here on out. I would have never realized this without a bore scope. That is one of the best investments I have ever made.
 

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Discussion Starter · #13 · (Edited)
Went to another match yesterday and it shot well and it went all day without cleaning. It was a unlimited sighter session match so I ran 69 rounds on it all shot at 200 yards on reduced targets for the 300/600 phase. I had a 99 on 300 and was clean for first 12 shots at 600 reduced and then the barrel heat started coming up through sight picture and I started losing them to elevation. Tried to clean the carbon out at range but bronze brush turned out to be crappy so I had to finish when I got home.

Did about three or four 10 pass sessions before I got patches to come out clean and dried it out good and went for the borescope.

There is just a very slight trace of copper first 6" and last 16" just a slightly more here and there which I was extremely glad to see it was not building up like I saw on the previous 229 rounds without defouling.

Prepped some more rounds last night to replace the ones I shot and checked the seat depth. Very interesting before the erosion gage showed movement and the seat depth didn't change.

This time the erosion gage showed about .005" movement but the seat depth went forward about .020". As before this is determined by soft seating bullets about .050 too long and chambering them and letting the bullet ogive place contact and force the bullet back down in case.

I also did a bullet measurement study (quick and dirty) using Sinclair tools. First I measured from the base of the bullet to the contact point on the ogive and this gave me a total difference of about .025". I noticed 2/3rds were on the lower end so I segregated them to one pile and the longer ones to another. The shorter ones will be used at 300/600.

Next I measured bullet diameters and they ran .3082 to .3088. Bearing in mind this barrel won't take a .2984 plug in muzzle that is a interesting squeeze down.

It gets worse. I measured OAL all seated with same seater and it varies about .025" difference. I took a case base to ogive reading using a Sinclair bullet nut and it measured all over the place as well.

The specs on the 173 Match bullet was .308 to .3089. I got .3082 to .3088 on the longer base to ogive bullets and the shorter ones (segregated for 300/600) ran .3083 to .3087 and the bases appeared to be more uniform in them as well.

Obviously this begs the question of how much variation can be tolerated in these bullets and why is there so much. It is because LC had four bullet machines turning out 173s and they are all mixed together for loading.

Larry Moore went to LC many years ago and he got a sample bullet from all four machines and he had them plotted on a 100 to 1 optical comparator and they were FOUR DIFFERENT SHAPES ! ! ! ! !

He had them run testing with bullets loaded off one machine and accuracy at 600 yards was about a MOA. There were five lots of LC 7.62 Match run LC 60-1 thru 60-5 and the military teams snatched this up quickly and it shot well. Then Larry Moore retired and LC went back to business as usual which means four different shapes loaded together and accuracy increases from six inches to about 12 inches at 600 yards.

With than mix in propellant weight variances, neck wall thickness seating the bullets off center in bore to start with and well it's not a pretty picture haha.
 

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Wow Humpy, I understand all you posted and am amazed at all the info. I was always under the impression that Siera was the better bullets along with Berger. There is alot more little guys making them at a premium. Does LC stand for Lake City? If so I thought they were a primo bunch. Would make sense to me to sell bullits from one machine instead of pooling them all together. Shows what I really know!! Good luck with the matches, sounds like equal parts skill and luck, Lou
 

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Discussion Starter · #15 ·
LRShooter, yep LC is Lake City out of Missouri. It is a GOCO plant, Gov't owned contractor operated. The new LC M118LR (Long Range) is loaded with 175 gr. Sierra MKs. The older plain M118 with 173s were the mixed bullet stuff. I don't even think they are loading it now. It was run by Remington for years, then Winchester got it by accidentally bidding too low and now Alliant is running it. The M118 was loaded with 4895 and there was some Special Ball Brown box loaded with ball propellent for a year or two. The M118LR is loaded with Reloader 15.
 

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Yes ER is the same or rather close to it. I don't put the acetone in the stuff I make. Just Mercon Dexron, K1 Kero and mineral spirits. I make it 1.5 gal at a time.

!
Thanks for a great post/thread Humpy. I will be reading this one again and also the other thread/post you wrote.

I have a couple questions:

Would you mind sharing your formula for ER that you mentioned above? PM is fine if its a secret?

I'm not dead certain what you are refering to concerning "rings"? Are you talking about counting the ring groves of the riflings from the chamber up?

I have to admit I've never done too good of job keeping my brass cleaned on the inside, mainly because of a top notch gun smith told me the inside didn't matter much. His idea was that the carbon acted as a lubricant and aided the bullet in smooth release. But after reading your findings I have little doubt that my gunsmith was dead wrong, and you are right.

I also like the fact that you use a primer pocket uniformer to remove the carbon. I've
almost always done that, but I was doing it for a uniform seating depth for the primer.

Thanks again for some great reasearch and writing. :)
 

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Humpy, thanks for the outstanding info. I have two new barreled actions on order; let's just say that my approach to cleaning is going to change completely! If you do not mind sharing the formula for the solvent you mix it would be greatly appreciated.

One question, does the mix you use work well on copper as well as carbon build up?

Thanks.
 

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I recently read the "The Carbon War Chronicles". As a result I gave Mobil 1 a serious workout. Its been 48 hours since I soaked 3 old mil-surplus rifles barrels with Mobil 1. Thus far I found no evidence that there was any hidden carbon residue in any of them even with bronze brushing. My conclusion is I'm sticking to Eds Red. I'll continue to use the Mobil 1 as a general purpose lube for my guns, presses and tools.
 

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Discussion Starter · #20 ·
Ed's Red Formula I use:

2 qts Mercon Dexron Transmission Fluid (note cheaper to buy a gallon at Wally World in blue jug)

2 Qts K1 Kerosene. (note I have also used diesel fuel and also works well)

2 qts Mineral Spirits which is a high grade paint thinner. Sherwin Williams Paint has sales on 5 gal buckets of genuine Mineral Spirits at times and I got one at a good deal a couple years ago and still working off it. I think it was a spring sale???

I mix it in a 2 gal Blitz Gas Can.

I also put a pint in my vehicles occasionally.

sorry for delay answering but apparently I don't get notifications when folks post questions to me on my regular email list.

Anybody know how I can get notified when someone responds. It is embarassing not to respond to folks in a timely manner.
 
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