Is this C# action method code actually firing a 301 redirect?

Here is the code I use when someone visits a product page on my ecommerce website. ``` public ActionResult Details(int id, string slug) { using (var productRepository = new EfProductRepository()) { var product = productRepository.FindById(id); if (product == null) return RedirectToAction("Index", "Home"); if (product.SeoTextSlug != slug) return RedirectToAction("Details", new {id = product.ProductId, slug = product.SeoTextSlug}); var model = new ProductDetailModel(); //Load the product information. model.Product.ProductId = product.ProductId; model.Product.CoverImagePath = product.CoverImagePath; model.Product.Name = product.Name; model.Product.Tagline = product.Tagline; model.Product.Price = product.Price; model.Product.Stock = product.Stock; model.Product.PieceCount = (int)product.PieceCount; model.Product.SKU = product.SKU; //Load the reviews for that product. if (product.Reviews.Any()) { foreach (var review in product.Reviews) { model.Reviews.Add(new ReviewModel() { ReviewId = review.ReviewId, AccountId = (int)review.AccountId, Content = review.Content, Location = review.Location, ProductId = (int)review.ProductId, PublishDate = review.PublishDate, ReviewRatingId = (int)review.ReviewRatingId }); } } return View(model); } } ``` In this bit: ``` if (product.SeoTextSlug != slug) return RedirectToAction("Details", new {id = product.ProductId, slug = product.SeoTextSlug}); ``` Am I actually firing a 301 redirect correctly? Sure it's working as I want it to, but I want to make sure I'm returning a correct standard HTTP result so search engines properly respond to it.