Headspace issues with Contenders are very real, and date back to the Herrett wildcats when new reloaders didn't understand the importance of setting the headspace of formed cases to match their chambers. T/C did indeed have some chamber headspace measurements out of spec - two .30 Herrett barrels I had varied by 0.006" from each other. It didn't help that some die makers cut their FL sizing dies too short either.
Some have reported issues with the .35 Remington too, but this happens with other makes of rifles too, at least occasionally. The .35 has a small shoulder and it is easy to set it back too far with some die sets.
In all the years I shot silhouette I don't remember anyone complaining of problems with the 7 TCU...
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