Has anyone used one of the rifles that have aluminum receivers? In these rifles the bolt locks directly into the barrel so that there is no stress on the alloy receiver, but I wonder about the constant friction between the bolt and the receiver during cycling. Do they develop wear or play with use? Any information about such guns is highly valued.

Does an AR-15 count? Aluminum actions are anodize leaving a very hard surface.
There are custom bench rest actions as you describe and if they had issues with wear and accuracy loss no one would use one.

Mark

I have a Sauer 202, it is similar to the Browning in that it is a fat bolt system. And different in that as you say the bolt locks into the barrel.

There is nothing wrong with it, and the bolt does not wear on the barrel.

ar 15,ar10 variant BLR, 10-22, marlin 22s, an some no-name import shotties... and a bmg single shot

so, yeah, i have.. and it depends ...

Hard coated aluminum is harder than steel.

Maybe on the surface but pound each one with an ice pick and see what happens. Anyway, harder does not mean stronger or we would be shooting rifles made of quartz. On the Mohs scale, hardness of knife steel is about 5.5, a steel file is about 6.5, and quartz is 7.

The M16/AR-15 is a perfect example. The steel bolt locks into the steel barrel extension. The bolt rides in a steel bolt carrier. The steel bolt carrier forces the steel hammer back. The steel bolt carrier rides back into an aluminum buffer but the buffer moves and shock is taken up by the buffer spring. So the hard wearing parts are all steel.

The Beretta 92 pistol is another example of using both steel and aluminum parts. Again, the parts that take most of the hard forces and heavy wear are steel on steel.

The Colt New Agent has a steel slide and an aluminum frame. The manual cautions AGAINST honing or polishing the feed ramp. Doing so, it warns, will remove the durable hardened aluminum surface and leave a soft aluminum feed ramp.

quote:

Originally posted by adrian4444:
Has anyone used one of the rifles that have aluminum receivers? In these rifles the bolt locks directly into the barrel so that there is no stress on the alloy receiver, but I wonder about the constant friction between the bolt and the receiver during cycling. Do they develop wear or play with use? Any information about such guns is highly valued.

The best example that I have for this would be the Stolle Panda action. It has an aluminum receiver with a steel bolt, and steel insert for the locking lugs and threads. Wear does occur under the rear bridge, as this is where most of the contact occurs during bolt cycling. This wear is minimal however. Benchrest shooters put many thousands of rounds through these rifles, and while most of us are using all steel actions now, I know of Panda actioned rifles that have 100K+ rounds through them with minimal wear to them...

I have a coupe, of Merkels: a K1 single shot in 7mm RM and a Merkel Helix.

In both cases the actual bolt lugs are steel locking into a steel barrel. The action merely holds the stock in place.

I have no worries about the durability or the accuracy of either.

Don't confuse wear with hardness.
Feed ramps ? My friend complained that his High Standard pistol [original] had a feed problem . The magazine follower was zink and the brass 22 case was enough towear the follower.As he was a machinist I told him to make a steel follower !

As long the bolt locks into the barrel, à la Sauer or Blaser, there is a steel "bridge" with no loss in strength or rigidity.