This will sound hysterical, but there is the risk of a Garand type mechanism ejecting the bolt into the shooter's eye during an out of battery situation, or at least, an in battery slamfire where the mechanism is partially locked.
Sammy, our last WW2 veteran, ran matches and participated in high power matches for years. When it came to selling off the Club's Garands, which were bought from the CMP in the 1960's, Sammy was the property book Officer for the club, and it was over to Sammy to pick up a rifle. One I handled, was in very good condition and was almost all matching except for the bolt. Sammy told me that was the rifle he earned a Master's card (in the early 1960's). And, the reason the bolt did not match was because the original bolt came out of the rifle during a 300 yard rapid fire event. The Armorer on the line decided the ejected bolt was defective and put in a new bolt instead, and Sammy continued shooting. The rifle was not damaged in any way and Sammy was concentrating on sight alignment and trigger pull, so he had no idea why his rifle kicked out its bolt on the firing line. And I was also pretty baffled by the concept.
But later I remembered a post I read about a Marine shooter's M14 ejecting its bolt into the forehead of the shooter, at Camp Perry, during prone rapid fire. The poster claimed all the NM ammunition was withdrawn from the line and a new lot issued. The Marine shooter was not hurt badly enough to not continue shooting, and the whole National Match continued on.
I also read a post by
@Hummer70 in which he states American dead in Korea were found with carbine bolts in their foreheads.
Just this year, I re verified an account with a USMC shooter. He was a USMC Rifle team shooter in 1972, and he showed me a picture of his team, at Camp Perry, just after his team won the 1000 yard match, with M14's. The M14's and the Campaign hats were very predominate in the picture. (P.S. the military teams create several sub teams from their members, so you will see a USMC Gold and USMC Silver or USMC Red and USMC blue on the firing line during team events.
Anyway bud told me of two incidents he personally witnessed where M14's puked their bolts out into USMC rifle team shooter's eyeballs. He said the rifles were damaged, and that one shooter lost his vision in his shooting eye, and the other shooter was severely hurt, had to be hospitalized, but evidentially kept his eyeball. These were military rifles, built by Marine Armorer's, using military National Match ammunition. Bud had no idea why these events happened, and I am going to tell you, the military does not spend any time teaching their people about rare failure mechanisms which might reduce the faith of the shooter in their weapon. I found this policy going back to the early 1920's. Which was probably when it was recognized that the low number M1903's had a high rate of receiver and bolt failures.
Out of battery slamfires end unpredictably, and I don't know all the failure mechanisms to an inbattery slamfire. I have no doubt an partially locked in battery slamfire would over accelerate the bolt to the rear, and that could have been what happened to Sammy's during his rapid fire sequence. An out of battery slamfire is far less controlled and if the bolt is pushed to the rear, at a full 50,000 psia, delayed only by its weight and an inconsequential operating rod spring, that bolt has a lot of places it can go. With straight back being only one possibility.
I believe it is only prudent to use the least sensitive primer consistent with reliable ignition, in a Garand type mechanism.
And always, wear your shooting glasses!
