Yes generally speaking, the Stainless Barrels are more accurate than the others. That is why the companies use them for the match, varmint and predator barreled rifles. And most quality rifles of this type have the Wylde Chamber in them. However, the durability is not as good if you are going to shoot an excessive amount of rounds or a lot of rounds at one time causing excessive throat heat and erosion in the barrel. In terms of durability in order that are 1. Chrome Moly 2. Chrome Moly/ Vanadium, and 3. Chrome Lined is even more durable in the Chrome Molys and should always be used on select fire weapons, those who are going to experience excessive shooting for prolonged periods as well as those in Salt Water or High Humidity environments and 4. Stainless Barrels.That is why the match shooters at Camp Perry change them out after about 6-8,000 rounds. For you and I that would not be necessary unless we abuse the barrel.
As Alsquar stated I too had a Sako Rifle and had shot a lot of 5.56 rounds through it also. But as he stated a Sako Rifle's quality of steel and craftsmanship is far better than most production rifles. Once in a while my bolt had a slight bit of resistance when finally closing into battery. It was years ago and I did not realize what I was doing by doing that! Lucky I guess and glad nothing bad happened! The Sako obviously handling the pressure spikes we previously spoke about. And also as previously mentioned if a 223 Chambered weapon is not Chrome Lined some minor 5.56 chamber reaming can correct the problem and issue. But as a general rule, one should not shoot 5.56 NATO ammunition in a 223 Remington chambered weapon. Although I think? some manufacturers may be using a NATO chamber in their rifles or most likely a Wylde? I just wish they would advise in the documentation of the weapon. That would certainly help! I guess the only way we would know was to call their company technical department. Most people there on the normal phone contacts do not have that much technical knowledge of the product.
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