QUESTION ON Archer Airguns CAR78a Air Rifle

[HILMAN76]

Does anybody own one of these in .22 or .177? What type of tuning is possible with one of these bad boys? does an extension tube work on a carbine version? Thank you guys in advance for any info..:emoticon:

[SDale]

The same tuning for a QB78/79 will work with a CAR. The CAR is just cosmetic. Slightly shorter barrel, large bolt handle and a muzzle brake. That's all.

Not sure what you mean by tube extender?

[HILMAN76]

IT LOOKED LIKE A CO2 TUBE EXTENSION.MAYBE SO IT HOLDS MORE AIR? IM NOT FAMILIAR WITH THE PROPER TERM, BUT IT WAS HOOKED UP TO WHERE YOU PUT THE CO2 TUBES. IT WAS ABOUT MAYBE 2 OR 3 INCHES BUT IT DIDN'T LOOK LIKE AN CO2 TANK. AND IT WAS BLACK.(IM A CONFUSED NOOB?)

[HILMAN76]

IM NOW DEBATING ON THE CAR78 OR THE                            Archer Airgun QB79 Custom Air Rifle..either one i purchase ill give Mike M. a holler to tune and work his magic.. I like the fact i can put the 88oz tank on the qb79 so if i tune it for higher psi I have more shots.. :emoticon:  :emoticon:  :emoticon:

[patton123]

Go w/the QB79..... better barrels. I have both 78 / 79  I'll grab the 79 every time. When you decide to bite the bullet, just buy the gun from Mike M. and have him tune it.

Good Luck.

[HILMAN76]

THANKS.I HAVE MADE UP MY MIND AND IM LOOKING AT A QB79. I WANT THE BARREL SHORTENED TO WHERE THE 88GRAM TANK SITS FLUSH BEHIND THE MUZZLE BRAKE.IM FOR SURE LOOKING AT HAVING MIKE M. BUILD IT.

[patton123]

x

[cole5169]

Here's my take:

I have one of Steven Archer's CAR78A's in 0.177 caliber.  I also have a QB79, and an AR2079, both in .177 (and several other QB's in both .177 and .22, but they aren't considererd in this post...).

All three are comparable in power.  The AR2079 is the tack-driver of the bunch, but I think that is due more to the stock geometry and balance (in my opinion, the barrels are all pretty accurate).  My wife and I trade it back and forth to shoot 0.68 cal paintballs off of golf tees at 30 meters with the diopter sights.  Yeah, it's that good.

Other than barrel length (and a shorter forestock on the -79), the most noticeable difference between the CAR78 and the QB79 is the shot count.  I go months and months between refills on the -79.  After about 4 powelet changes on the CAR78, I decided that I was done with powerlets, so now I use a bulk-fill cap on my CAR78Ar, also from Archer's.  The CAR78 is actually a better shooter than the -79, again, I think due to balance.  I use a 9 oz tank on the QB79; with that and the long barrel (and add a few ounces for a brake...)  I get a lot more muzzle swing when I shoot unsupported.

I wish I could remove the muzzle brake from the CAR78, but it's on there pretty good (epoxy, maybe?).  At first, this worried me, since I couldn't inspect (or improve!) the crown, but it turns out that mine must have a pretty good crown anyway because it shoots so well.

I find the CAR to be very "pointable"; it's light, quick to get on target, reasonably quiet, and terrifically accurate.  The CAR78 is one of my "go to" guns when I just want to enjoy myself in the backyard.  With a red-dot scope or a bug-buster, it's a great little package.  I want to go ahead with making a garage-built .22 version, probably using one of my under-utilized QB78D's as the donor platform.

Sounds like you've decided on the QB79, and it's a great gun, you'll enjoy it.  

[HILMAN76]

I still Haven't made the purchase yet. I change my sock's like I change my mind,more than once so i don't get fungus

Its still on my list but the list just keeps growing and growing.

I started looking at the mountain air qb78 custom by roy. http://www.mountainaircustomairguns.com/model_12.htm

[HILMAN76]

Oh yeah, i have been eying this crazy lil beast also http://www.mountainaircustomairguns.com/model_13.htm

My list of dream AG's keeps growing and growing..All I need is the CA$H

[patton123]

You still don't have a QB79 :emoticon:  Whats going on??? I thought I made up your mind..LOL


Seriously.....Buy a Beeman.  :emoticon:

[triry]

cole5169 - 8/29/2009  6:34 AM
Other than barrel length (and a shorter forestock on the -79), the most noticeable difference between the CAR78 and the QB79 is the shot count.  I go months and months between refills on the -79.  After about 4 powelet changes on the CAR78, I decided that I was done with powerlets, so now I use a bulk-fill cap on my CAR78Ar, also from Archer's.  The CAR78 is actually a better shooter than the -79, again, I think due to balance.  I use a 9 oz tank on the QB79; with that and the long barrel (and add a few ounces for a brake...)  I get a lot more muzzle swing when I shoot unsupported.  

joel.....using the bulk fill adapter on the 78,.....how do you determine c02 fill level ?

[cole5169]

Well, I don't try to "get as much fill as I can", because I'm comfortable with just about anything over 50% rated fill.  It's no problem to add more gas when I notice the power dropping, and I get a lot of fills from standard 20 or 24 oz paintball tanks.

First off, I ONLY fill the gun when it and my donor tank are at the same temperature (and that's usually "room temp", about 20-25 degrees C).  At this range of temps, the pressure in either the gun or tank will be between 850 and about 925 psi, and not nearly enough to rupture the blow-out disks on my tank or fill line.

Filling tank-to-tank at the same temps (or in this case, tank-to-gun), you can't get MORE pressure in the gun than there was in the donor tank to begin with.  In fact, the pressure in the gun will be a little bit less, just because it is stealing volume from the donor tank, and the pressure between the two will equalize.

So, if your donor tank is at or below 100% rated fill (7/16th oz CO2 per cu in), your gun will be too.

What I do is this:
I set my gun(s) on the floor, standing up vertically with the fill adaptor as high as possible.
Attach the fill line to the tank and to the gun's adaptor.
Turn the donor tank upside down, to allow liquid CO2 to transfer.
Open the valve on my fill line and transfer CO2 for several seconds until pressure equalizes (with my fill apparatus, I can hear the transfer).

When the liquid CO2 enters the gun's gas tube, most of it flashes into vapor (because the pressure is intially so much lower than in the donor tank).  As the pressure between the two equalizes, more of the transfer is liquid.  This takes only a few seconds.

Now: with the valve left open, I turn the donor tank right-way-up, and walk away for a minute or so.  This is just for my peace of mind, because I know, deep down, that the laws of vapor pressures and equilibrium don't need for me to allow time for equalization of the vapor/liquid partitions.  But still, that's how I've done CO2 bulk fill for years, since waaaay before I went to university and got a degree in physics...  Back then, I was afraid I would accidentally "cram my gun full of liquid CO2 only", which WOULD be bad.  Now I know I can't possibly do that (without seriously chilling the gun and probably using a pump to transfer...), so I shouldn't worry, but it doesn't hurt to let it sit, and it makes me feel safer

Always use equipment with burst-disks.
I say don't chill your tanks or guns before filling them to try and get >100% fill...  Probably because I am a chicken