I have been shooting the same .338 Lapua cases now for about 5-6 times without trimming the brass. I went to the range today and found that my groups started growing dramatically since they were fire formed. Trim length is recommended to be 2.714". Measuring the cases after I fired them, I noticed that the average length has grown to 2.737" and a couple rounds didn't allow the bolt to close easily. Will this cause excessive pressure spikes, and as a result have a significant impact on group sizes?