I'll be getting 3 replecements from Umarex either late this week or next.
I'll let you guys know what they are like.
One is in 177 and two in .22.
I can't wait to get this .22 I have here converted and ready to ship.
I started work on the 177 for Rich, it's sweet right out of the box and
shoots really well. I think we have a really good foundation here..   

The 850 Store

..at small rocks (size of walnuts) at 40 yards with my tuned 850 CO2 .177..rarely miss....I do this if I get bored hunting squeeks sometimes...key here is knowing your rifle trajectory and dope for various ranges...and I think these barrels are truely remarkable given price of the 850..

These CO2 rifles shoot very consistantly from 60F-90F using the heavier hammer spring to prevent valve lock at 85-90 F...in otherwords,there is very little poi shift from 60F-90F which debunks the common assumptions about "temperature" sensitivity....certainly,there will be affects(lower pressure at 50 F...and higher pressure at 90 F....

BUT:

Ouote:

"Valve duration is simply a function of the available CO2 pressure which influences how fast it shuts. Higher pressure shuts it quicker so a relatively consistent output can be had from quite a range of pressures."

Unquote..

Can't wait to shoot the 850 HPA Roald is tuning for me....been doing push ups to get ready and do my first fill with a pump...LOL..

Rich,

If you are getting a 22ci. tank going from 2k psi to 3k psi isnt too bad. I have lost count of how many fills I have done with my....oops Roald's Disco pump. And I can honestly say that after putting the new O-rings that Gary Hurley on the crosman/benjy pcp forum sold me in the pump and relubing with Mac1's secret sauce it is a really slick pump now and filling is painless. When I first put the o-rings in I used the plumber's silicon grease that the guys over on that forum suggested. It worked ok but it wasnt optimum so after reading some of Tim's posts on the green forum I decided to try some of the Mac1 lube in the pump. So far so good and wow what a difference. You will enjoy the hpa'd 850 it is just a cool deal.

John

The 850 Resource

I've noted your reference to Gary's o-rings...and have Tim's sauce...so far my pump is doing great...and have only used it going from 1K to 2K in the Disco...pump will be year old in September...time for some maintenance..
I take the Benjamin Tank and two tins of pellets plus my Marine Kabar hunting in the field in case my position gets overrun by squirrels.....ha ha ha ha..

Well they are here..... I will test them out and let you guys know what I find.
Although I must say that first impressions are that they all (including the 177 barrel)
have tight spots at the second to front sight hole....
WATCH THIS SPACE  

The 850 Store

Roald...are these barrels choked..?? Because that is done near end of some barrels by about 1000th/in+ or so...idea is to get pellet on a truer path out the barrel...be nice if they were...

Been wondering what Umarex says about that...

Yes they are choked, but these "constrictions" are at the first front sight hole
from the breech end. more than an inch from the muzzle.... then the choke is still
there right at the end of the barrel.
Well shooting will reveal the truth I guess. I have a comment on the packing slip that
each barrel was tested and produced a 1/2" group, no distance was provided though.
We will see soon enough.

The 850 Store

..as a good indication on a barrel...both my .177's do really good at that range...when i get my benchrest done tomorrow,I can do some more thorough testing..

1/2" at 40 yards would be good. 1/2" at 10 yards would not be so good. Can't wait to see what you get from the new batch of barrels.

Has any one cut the barrel right after the front sight screw hole? I bought a gun with a bad barrel and was just thinking of sending it to Roald and while I hade him do the tune just cut the barrel and recrown it. Looking at it its less than 2" so would this little be a good trade off in power for accuracy. Any way I hope the new barrels work so I dont have to consider this but if not I will take a slightly shorter 850 instead.

Eric

Think I would try "lapping' barrel first before cutting it...be worth a try on one of those bad ones....

Need barrel off rifle..Clean first...then use lapping compound...about 20 strokes WITHOUT pulling thru crown until last stroke...clean barrel again...test it...
Often,commercial barrel bores are NOT hand lapped or polished...usually just custom barrels are...

Well I've tested 2 of the three replacements.
One is "okay" not great, not displaying the accuracy that got me into the 850's,
but acceptable.
The second one sucks. It'll produce loose groups and even the occasional "Good"
8 shot group, but mostly 1" or more at 18yards.
I have not tested the 177 barrel yet only because I have no "spare" 177 to test it on
right now, but because it too has the tight spot at the first front sight hole, it'll not be
very good either, I don't have to test it to know that.
So it looks like all the 850's  (in 22 at least) are going to have this issue going forward.
This means the The 850 Store will no longer be able to guarantee accuracy of the
850 like it has in the past.
This is a shame, it was such a good gun for a while there.
I will try and get LW barrels for the last few I have, but that will add at least $120 to
the price and... well thats an ass load of money to put it bluntly.  


The 850 Store

I'll be seeing Tim Mcmurray (MAC 1 owner) at a match I shoot in July 19th...think he said there is a shipment coming his way...I'll check his price,but think it's $75...and these are blued..

Rich

Edit: Barrels are clearing customs this week to Tims shop..MAC 1..

15mm...$85...blued and crowned...
16mm...$105..ditto..

I just got done doing the port mod, and then i pushed a pellet down the bore through the chamber side. There was a tight spot right at the rear front sight hole, the hole that isn't even tapped. there is also a tight spot right at the rear site tapped hole. the gun is a .22
The tight spot isnt as apparent if the pellet is pushed through the frot of the barrel, but is still there.

I haven't yet shot the gun, although i did get it for Christmas (was waiting for scope funds, plus not many places to shoot it here) it was an old gun when i got it from pyramid and had some light surface rust on the barrel. The serial # is G014591

How far back does this problem go? when i ordered my gun i didnt hear of any complaints about it. Will umarex replace the barrel if i have used steel wool to take off the rust, then a cold bluing compound on the barrel, and then did the port mod? i would think that would have voided the warranty, even though its quite apparent that i wouldn't be the one responsible for the tight spots.
also, I havent seen anywhere on umarex's site about the recall or notice about the bad barrels. I havent even seen any official statement about the problem (which it seems they still have.. sounds to me like they need to sharpen their drills more often, or use shorter bolts)

Thank you

-Brian Barney

Try shooting it first for groups @ 25 yards or more with good pellets and see how it groups. I have a replacement I had to pay around $80. shipped for if I remember correctly because I modded my barrel before I found out it was bad. The new one has a slight tight spot only at the front sight screw hole with CPs because they fit the bore tighter, but with JSBs it not very noticable, but this barrel groups very nicely @ 25 yards. So I would shoot it first and see because your going to pay for a replacement because you modded the original. Good Luck

Ok, so there is no free replacement after its been ported. thats what I thought. If this does group poorly, are there replacement barrels from other manufacturers? I prefer stainless as there is less to take care of. I know somebody mentioned LWalther might be making some for the 850? I would like it without the site holes drilled as i plan on only using a scope for this gun.
Thank you,

-Brian Barney

LW makes 15mm barrel blanks as well as HW, but they are just a blank that run $110.-$90. shipped and then you have to send it out with your stocker to have it machined to fit, which runs another $45.-50. and also neither is S/S. The LW is bare metal and the HW is allready blued. Either way it's expensive and not really needed if you have a good stock barrel because they group very well. With my bad barrel it was as you described it had two tight spots front and rear so there's a good chance yours is bad. I would just buy a good replacement from Umarex, they are only around $90. shipped and when you have a good one it groups very nicely. Good luck and keep us posted on what happens.

but it seems like we have the same problem in the U.K i have tight spots just at the rear and front sight holes. i called to tell brocock (the uk agents) about it and they would not listen to me. and they would not replace it as it's now "out of warranty". the reason i didn't pick up on it for a year now is that i only used the 850 twice in the field. now its a project gun but i wont it to shoot well when i'm done with it. has any body got contacts in the u.k for an LW or HW barrel ? we can get hold of the blanks but the machining is the problem.

If not Roald how many requests for LW or HW barrels will be needed to make this barrel system go-able?

I checked the owners manual and it does say one year waranty. That sucks. Also did you test for grouping at a decent range? Tim @ Mac1 might be able to ship you a new HW blank.

yeah i tested grouping at 30 yards there is no way i am that bad a shot and even taking into account CO2 dynamics that would not explain the results
let's just say it was bad.

So Tim at Mac1 might have some blanks than dose he machine them up for the 850 too?

I had a quote over here from a guy that wanted £260 to supply and machine a hammerd BSA one up i told him that was more than a new gun. i did laugh when i got off the phone.

Call and talk to TIM....you may have to ship a "stock" barrel to TIM to get one of his HW blanks machined to match the 850 barrel...he has seen my 850 HPA at matches we shoot at,but don't think he has worked on one...and I have not talked with him about HW barrels yet as mine stock barrel(s) are doing just fine...

PHONE 310-327-3581 FAX 310-327-0238

Can machine it for you, but if you want it blued it will have to be sent out for that as well. RIM or Greg can cold blue it also. I have one and it was expensive $112. for blank and $45. for machining and another $45. for bluing for a total of $202. and that is without the shipping for maching and bluing so grand total of $226. ouch but it is vary nice and is going into a HPA set up. Tims barrels are allready blued so if you use his it will be at least $50. cheaper, around $150.-175.USD.

I emailed Tim yesterday just waiting for a reply.
Hopefully postage to the U.K wont be to much.
$175 is a lot better than £200.
lets hope there's no stupid law attaining to barrels being posted in the mail to the U.K

thanks for Tim's contact details