I have installed quite a few and all have been perfectly fine. The barrels are properly stress relieved and there is no warpage when contouring. The bores are smooth and well finished.
The real test of any barrel is in the shooting and, to that end I ordered one for myself. The test was, ultimately, a bit unfair because I didn't opt to build a proven combination but elected to experiment a bit. A fair test of a barrel is to fit it to a known action in a proven configuration and chambering. This I did not do.
I shoot a bit of "F" class competition which is essentially, any rifle, any sight, fired prone with a rest at ranges from 300 meters to 1000 yds. I have used the 6BR, the 6.5x55, the 308, 30/06, and the 303 British (believe it or not) with varying success. Several years back a Texas shooter had used a fast twist 22-250 successfully and I thought I might try one and test a Mcgowan barrel at the same time. To this end I ordered a 22 caliber blank with an eight inch twist. I ordered the blank 30 inches long; intending to finish it at 28 inches. When I picked up the blank, it was plain it was not one of their best efforts. The bore was eccentric by about .070" at the muzzle end. Of the half dozen barrels I had bought from them, this was the first one which was not straight. In fact, all the others had been very good. This one was not. I cut it to 27 inches (One inch off the breech end, two off the muzzle) which improved matters, and turned it to a heavy varmint taper. Typically, it turned well with no warpage.
I threaded the barrel between centers and fitted it to a CIL 950T action (Savage 110 single shot)I had recently purchased. I had not fired the rifle with it's original barrel (a 308)so the action was untested.
Once the barrel was threaded and fitted to the action (without the Savage barrel nut BTW), I set it up in the four jaw chuck to chamber it. The bore was straight at the breech end and it was not too difficult to get the first three inches running true. I cut a standard 22-250 chamber but with a throat long enough to allow the 80 gr Sierra bullet to be seated ahead of the neck/shoulder juncture (I prefer this. Some don't care). The barreled action was pillar bedded into the original stock and the trigger set to 1 1/2 pounds. The rifle was ready for testing. I prepared some Remington brass (not the best choice but I had it), turning the necks enough to true them up. I made a new sleeve and seating punch for a Hornady seating die with the same reamer as had chambered the rifle.
I had no loading data whatsoever for the 80 grain bullet in this case so I just had to wing it. I started out with Varget which I figured was a bit fast but worth a try. 31 grains yielded about 3100 fps . Accuracy, while not spectacular, wasn't bad with five shot groups around 5/8 inch at 100 yds. Spread was mostly vertical. The barrel showed no tendency to foul and cleaned up well. I worked up to just over 3280 fps at which point a primer fell out. I took this to mean the load was bit warm and a sure indication that varget was indeed a bit on the fast side.
Next up was 4350. It got me over 3300 with no pressure signs but velocity variation was excessive and accuracy about 3/4 inch.
I then went to 4831SC. With this powder, accuracy was better and velocity variation not so bad (SD around 19fps) but out of each ten shot string there would be two shots which were way fast or way slow (by about 40fps). As I worked up, the variation got better until I had an SD of 10fps and an average velocity of 3350fps. Still the occasional shot would be outside the normal velocity range. Ten shot groups at 300 meters were decent but not exceptional for an "F" class rifle.About 2 inches. In comparison, my best 308 will produce ten shot groups right around 1 inch at 300 meters. The 22-250's groups typically had seven or eight in a nice cluster of about 1 1/2 inches with a couple shots high or low. Since the 300 meter X ring is about 2 inches, this isn't good enough to shoot "possibles". This was born out when I fired it at a match and was unable to clean any ranges. Nonetheless, a sub 3/4 moa rifle isn't too bad.
As I said earlier, this was not a real test of the McGowen barrel. This particular barrel was sub-standard in comparison with the other McGowens I had used but, when I test something, I take it as it comes. Secondly, I was messing with an unfamiliar combination caliberwise. On top of this I was using an untried action. Nonetheless, the barrel performed quite well. It never fouled and was easy to clean. The velocity variations which limted the success of the whole project were not likely the fault of the barrel. In addition, I have received barrels which were less than straight from virtually every maker. If I am building a match rifle for someone else, I'll refuse the barrel. If I'm trying out a maker's barrel, I try what he gives me.
The bottom line is this; I'm satisfied with the McGowen product. The barrels are a good value. For a serious match rifle I'll still go with Hart, Shilen, or Krieger but for a hunting or even a varmint rifle, the McGowen barrels are good choice and I will continue to use them. I'll probably even try another in a 308 twelve twist. This one will go on a proven 40X platform and will perhaps, be more indicative of what the barrel can do. GD

Last edited by greydog; 11/15/08. Reason: typo